What is it about this one irrational number that makes tech geeks go nuts? Every year on Pi Day - that's today, March 14 (you know, 3.14) - there are Pi parties, Pi recitation contests and, of course, pie for Pi.

The whole thing really goes nuts on March 14 at 1:59 a.m. and p.m. local time - because, after all, Pi is 3.14159… The festivities - particularly the big mama of them all at the San Francisco Exploratium museum going on today - would make Archimedes proud. The ancient Greek mathematician gets credit for popularizing the mathematical constant, of which references can be found as early as biblical times. And Albert Einstein, born March 14, would be psyched, too. He couldn't have calculated gravitational field theories without Pi, now could he?

Check out the infographic below for a ton of facts about pi - the only error I found in it is the fact that Archimedes was its publicist, not its identifier. Pi is far, far older than even that ancient Greek. (And don't stop there, more Pi stuff below...)

Can't get enough? Try these Pi facts size on for size. There are Pi clubs around the world - including Japan - where people competitively recite as many digits of Pi as they can. I actually saw a guy named Koroyuki Gotu recite Pi from memory on stage at the NHK Broadcasting Center in Tokyo. It was at once fascinating and boring. In 112 hours, he recited Pi accurately to 42,195 places.

Did you know you can use Pi to calculate everything from the circle the size of the universe to the height of an elephant to your hat size?

Hats, Elephants And The Entire Universe

For the hat size, measure the circumferance of your head and divide the result by Pi and round it off to an eighth of an inch.

To figure out how tall a particular elephant is, just measure the diameter of its foot and multiply the result by two. Then multiply that result by Pi.

As for the universe, a mathematician I interviewed years ago told me it was possible to calculate a circle the size of the entire known universe down to a proton. And supposedly you'd need only the first 39 digits of Pi to do it. You can't make this stuff up.

There are also plenty of conspiracy theories surrounding Pi. With a number infinitely long, geeks are always looking for their own social security numbers, password ideas and repetitive structures that might suggest something strange is going on with this crazy constant. Some readers will be relieved to learn that Satan — if indeed the signature for the demon is 666 — doesn’t make an appearance until position 2240.

The most interesting thing to note about Pi is its amazing flexibility. Pi is employed in harmonic motion theory, superstring equations and, as mentioned above, Einstein's gravitational theory.

Pi Videos

As promised, here are a two videos that are perfect for celebrating Pi. The first shows Pi as it would sound to music. The second is an explainer of Einstein's relativity theory and its real-llfe applications. It is, after all, not just Pi Day. It's Einstein Day, too.

The sound of Pi:

Here's Einstein and the theory of relativity explained, excellently, by the fine folks at The Science Channel.

Happy Pi Day. And Happy Birthday, Dr. Einstein. Wish you were here.

Lead image courtesy of Shutterstock.

This week’s patent score:

Google: 27

Microsoft: 42

Apple: 18

Facebook: 0

Let’s take a closer look at some of the hits and misses behind those numbers.

Google Channels The Jetsons

Scanning through Google’s 27 awarded patents from the USPTO, new patent U.S. 8,261,090 stands out like a science fiction invention: It allows facial recognition check in and surveillance. Depending on your outlook, there is something distinctively Jetsons-esque about this – or it’s right out of 1984.

The deceptively dry patent illustration (below) describes the system. But a closer look reveals wide-reaching implications that are sure to get attention from privacy watchdogs.

Tom Ewing, a UN World International Patent Organization (WIPO) advisor and Silicon Valley IP attorney, said, “This is technology Mr. Spacely would use to make sure George is at work. It doesn’t cover facial recognition – but its combination of facial recognition (check-in telepresence) tech and audio allows Spacely to yell, ’Jetson! You’re not at your desk.’

“According to the patent, the system doesn’t just log you in with facial recognition," Ewing said. “It is possible to run it as an always-on system that will snap a pic any time an unauthorized user attempts to use the device.

“For example, if an unauthorized user attempts to log onto and use the computing device but fails, the camera records an image of the unauthorized user and stores the image in RAM, EEPROM or traditional storage. The ‘090 [patent] even covers instant sending of automatic photos to any mobile device associated with the authorized user,” Ewing added.

The security and monitoring implications for this system are wide-ranging. Say you work at your office. Your boss would know when you’re in front of your computer. Consumer uses are equally obvious: Just your presence can wake up your enabled system. Presumably, it can wake you up, too. “Good morning, George. It’s Mr. Spacely. Get in here!”

Microsoft Owns Geo-Temporal Tracking

Like Google, most weeks Microsoft gets a big bundle of patents - and its 42 patent awards this week puts it on top of the charts.

US patent 8,260,775 is one that’s worth digging into.

Microsoft describes this innovation as a “geo-temporal searching tool” that will make life vastly easier for people trying to track you down. That means employers, the government, advertisers and, unfortunately, stalkers and angry ex spouses.

Clearly, another one for the privacy folks to track. This shot from the patent has a description below the fold that uses the historic composer J.S. Bach as an example of tracking over time and geography. It shows a select region of Europe centering in Bach’s home region of what is now Germany - and a time window from the years 1685 to 1765.

It isn’t hard to imagine all kinds of marketing scenarios that could make use of such data on real live social network users. Potential political, marketing and data aggregation uses abound.

Microsoft’s patent on geo-temporal tracking, as you can see, could conceivably show a location portion of a search interface - finding people by time and location. In the Bach example, you get search events in a visible window onscreen.

Apple Helps You Find Starbucks - Yawn

Apple, too, typically gets bundles of patents – new and assigned – every week.

This week one of its 18 newly granted patents - U.S. patent 83260320 - included a way to find Starbucks faster. Yawn.

Specifically, the Apple patented system describes a wireless access point that permits wireless communication devices, such as any mobile device, to connect to a wireless network using Wi-Fi, Bluetooth and other standards. The wireless access point connects to one or more other networks - relaying messages over a variety of networks and devices.

The prior art alone makes this one look almost too obvious. Searching on local businesses based on location on a mobile device hardly sounds novel. To be fair, Apple submitted to the patent office hundreds of prior art references. But this is the sort of thing the Electronic Frontier Foundation (EFF) sniffs out for its software patent killing project – redundancy of claims. Find its patent Tk project here.

Facebook Gets Bupkiss

Facebook received no patents on Tuesday. None. Zero. And that’s unusual.

Ever since its IPO in May, Facebook has been busy beefing up its offensive and defensive patent portfolio, even going for a vanity patent – the first patent Facebook CEO Mark Zuckerberg ever filed for. But this week? Nothing.

Aereo, the controversial Barry Diller-backed service that is streaming live and pre-recorded TV over the airwaves in New York City, is celebrating its recent preliminary court victory against 18 broadcasters by offering a free hour of service and new pricing options. But the real key for the viability of this high-flying IPTV startup in court might well be revealed in four patent applications filed earlier this year.

In March, ABC and 17 other New York City broadcasters filed a copyright infringement suit against Aero, claiming the service was essentially stealing and rebroadcasting its over-the-air (OTA) programming for its $8 to $12 a month Internet Protocol Television (IPTV) service.

Now in beta, Aereo lets Apple iPhone, iPad, Apple TV and Roku users access round-the-clock live and prerecorded over-the-air (OTA) TV channels on their screens. The company defeated a preliminary injunction demandedy by ABC et al in July that would’ve shuttered its service. As a result, the four patent applications it’s filed with the U.S. Patent and Trademark and Office (USPTO) are increasingly relevant to Aereo’s futre and this particularly nasty copyright infringement case.

“Typically, patents or patent applications have no relevance in a copyright infringement case,” said Tom Ewing, an IP expert who trains attorneys for the United Nations on IP matters. “But after this July 11 ruling, the case is becoming a different bird. That’s because the judge expressly signaled her interest in the technologies employed by Aereo, saying the details will decide the case.

“If in fact the four patent applications Aereo filed four months before the suit hit it accurately describe Aereo’s deployed technology in New York City,” he added, “then these patent apps could give Aereo a leg up.”

Aereo representitve Virginia Lam told ReadWriteWeb that they do. “On your question of whether or not our technology works as we have described, the answer is a resounding, yes,” Lam said. “In fact, the recent decision by Federal Judge Alison J. Nathan in favor of Aereo (denying a preliminary injunction that had been filed against the company) bears this out.”

In her July 11 order Federal District Court Judge Alison Nathan was explicit that the case is all about the technology: Is Aereo simply copying and redistributing copyrighted over-the-air broadcasts as ABC et al claims. Or is Aereo just providing people the equivalent of virtual rabbit ears to grab freely available material on the airwaves, as it claims. In her opinion, she indicated that the merits of the case will lie on whether the Aereo system can be considered “one” or “many” antennae.

According to the USPTO, patent examiners have yet to take a look at the applications. So it may be too soon to party. But early indications from Judge Nathan’s order signal that Aereo’s use of a tiny and separate antenna in NYC for each user “reinforce(s) … that the copies (of broadcasts) are unique and accessible only to a particular user, as they indicate that the copies are created using wholly distinct paths.”

The patent applications appear to support this provided, as Ewing noted, that Aereo is doing exactly what the patent applications say it is doing: Providing an antenna per user, ala rabbit years, just 21st century remote style.

The four filed patent applications show how the company would use a rooftop array of tiny, dime-sized antennae at its New York City building - and assigniing each one per user as his or her own remote antenna.

The system, at least according to the patents, is essentially designed to provide each user with his or her own remote antenna – one of the tiny ones in Aereo’s rooftop array of millions of them.

Here are the four applications Aereo has filed with the US Patent and Trademark Office:

Its application (20120129479)called “Method and System for Processing Antenna Feeds Using Separate Processing Pipelines” supports the idea that the system’s intent is to assign an antenna per user as opposed to just stealing, recording and rebroadcasting, as ABC and the other broadcasters claim.

Its application (20120127374) “System and Method for Providing Network Access to Antenna Feeds” describes how Internet users get access to live antenna feeds, which appearst to be consistent with what Aereo reps have described about the system in its PR materials and in court.

The same goes for its application (20120127363) “Antenna System with Individually Addressable Elements in Dense Array,” which describes in detail how the system assigns users to individual antennas.

Accessing the recordings users make with their Roku, Apple TV or other DVR is the heart of application 20120131621, titled a “System and Method for Providing Network Access to Individually Recorded Content.”

In New York City, Aereo currently offers 28 broadcast channels available over-the-air, including WABC, WCBS, WNBC WNYW-FOX, WPIX-11, WNET-PBS, Telemundo Univision and other special interest and foreign channels.

Aereo plans to extend the service to PC and Android users in New York City later this quarter, and enter other markets in the United States in 2013.

This should be be an interesting case. It is a rare copyright infringement case that hinges on technology, much less patents. And the stakes are high.

Barry Diller photo courtesy of James Duncan Davidson/O'Reilly Media, Inc.

Lead Barry Diller photo by FOUNDERSclub NYC

In the last few months, Facebook CEO Mark Zuckerberg took his company public, got married and scored a nearly $6 million home loan at just over 1%. What could possibly top all that? How about approval of his very first patent request from way back in 2006 - covering privacy issues no less?

Turns out the US Patent Trademark and Office (USPTO), though it originally rejected it, just granted Zuckerberg a patent that can only be described as the ultimate geek vanity trophy.

A solitary patent repeatedly originally attacked by examiners for its obviousness, this one little patent certainly won’t help Facebook defend itself in patent spats like the it was recently engaged in with Yahoo. In today’s tech patent wars, you typically need entire portfolios of offensive and defensive patents to make a difference. But at least one IP expert said Facebook needs all the patents it can get. The company is likely feeling vulnerable after the Yahoo situation.

This new patent is mostly a fancy accessory for Zuckerberg: It’s US patent 8,225,376, the first patent application he ever filed. Zuckerberg filed the application back in July 2006, the year he turned 22. He's apparently earned at least half a dozen other patents since then, but now he's finally seen his first application approved.

The patent, called “Dynamically Generating a Privacy Summary,” is described in its abstract as:

… a system and method for dynamically generating a privacy summary is provided. The present invention provides a system and method for dynamically generating a privacy summary. A profile for a user is generated. One or more privacy setting selections are received from the user associated with the profile. The profile associated with the user is updated to incorporate the one or more privacy setting selections. A privacy summary is then generated for the profile based on the one or more privacy setting selections

Basically, the patent - narrowed from its originally overtly “obvious” claims as recorded by patent examiners - covers a method of displaying a social network user’s profile per his or her privacy settings, display them on screen and show what their profile looks like on-screen to various other users or groups of users.

The patent is broad. The USPTO issued it only after curbing claims 1, 8 and 16, which USPTO patent examiners originally rejected because of obviousness.

According to public records, the Patent Office rejected the original, July 2006-era, Zuckerberg patent application. That didn’t stop Facebook - at least not forever. The company redoubled its efforts to get the patent through just days after it announced on February 1, 2012, that it planned to go public. The company requested and received numerous interviews with patent examiners regarding what it could do to get this patent through.

Facebook initiated an interview to re-initiate investigation of the rejected patent application on Valentine’s Day 2012, shortly after it announced its upcoming IPO. Records from the USPTO show Facebook’s enthusiastic and persistent attempts to adjust and get that first Zuckerberg patent issued. And the effort finally paid off. According to IP experts, it's not uncommon to persist in getting a patent. If you stick it out you can get something issued.

The Zuckerberg patent is separate and distinct from the enormous patent portfolio Facebook is now in the process of assembling, in part to defend itself from patent infringement lawsuits like the one it just settled with Yahoo.

Shortly before it got involved in the Yahoo patent fracas, Facebook began buying hundreds of “just in time” defensive patents. Those efforts include purchasing hundreds of patents from AOL via Microsoft – for which it paid an estimated $1 million per patent. The USPTO patent assignee database reveals that than 500 patents (512) came to Facebook direct from AOL with the last week.

Of course this one vanity patent won’t provide the firepower of the huge portfolio of outside-invented patents Facebook is buying now. It’s really little more than a trophy - and it's a touch ironic that it covers privacy issues, an ongoing source of controversy for Zuckerberg and Facebook. But it’s worth noting how much effort Facebook spent on acquiring what is essentially a vanity project.

Facebook did not immediately return requests for comment over the weekend.