FriendFeed, a cross-network activity aggregator built by ex-Googlers and more fun to use than the phrase "cross-network activity aggregator" might imply, launched a powerful new search tool today. Want to discover particularly interesting conversations or people in your networks? Want to pick out just the noisiest conversations online about your brand? Want to find some really crazy stuff that's only discoverable through FriendFeed? The investigative possibilities that FriendFeed now offers are quite impressive, if you can bring just a little creativity to your search query construction.

Here are our favorite examples of some of the searches we've already found quite valuable.

The New Search Options

As you can see from the screen below, the new FriendFeed Advanced Search options are quite granular. You can limit your search to particular sites like Facebook, Amazon or any of 50 other sites supported for import. You can search your network of friends or the site at large. You can set a popularity threshold by number of comments or "likes." There are lots of options. All searches have RSS feeds for their results.

Brand Monitoring

For most people, tracking conversations around a brand name will probably be the most useful function of the new FriendFeed search. We find that relatively boring, so we'll get it out of the way first.

Mentions of "Sun Microsystems," system wide, with 3 or more comments.

Obviously FriendFeed is quite small right now so this isn't a comprehensive web-wide conversation tracker, but these search results could help point to issues that are catching part of the public's imagination enough to discuss. There are less than 1 million people using FriendFeed so far.

There are other searches that can provide more tangible value right now, even without a large number of people yet using the service.

Well Placed People

Location declarations through Brightkite, from friends of Creative Commons Foundation CEO Joi Ito, where 3 or more people "liked" the location statement or description. Chris Messina excluded, in order to see more of other people.

Your Wittiest Friends

Comments by my friends, tracked by Backtype, with 3 or more "likes." I've subscribed to this feed as there are some important details here that I wouldn't have wanted to miss. If you haven't signed up for BackType, or haven't tied it to your FriendFeed account yet, you should. It's easy to do.

Hot and Topical

FriendFeed rooms are a place to discuss a wide variety of topics. Here's some of the most commented on items in the Green Tech room. Find someone who made a great comment here? You can also search for all the rest of their comments.

The Hottest Events

What events are the cool kids going to, that their friends think are particularly cool? Here's events that friends of crafty inventor Bre Petis have said they are going to on Upcoming.org and that their friends have "liked." Robert Scoble excluded for the sake of seeing other people.

What Else Can Be Done?

Those are our favorite examples so far, but we're sure we'll come up with some more in the next few days. The FriendFeed search back-end sometimes barfs if you search friends of very popular users, but it seems to be holding up much better than it was a few weeks ago.

We love FriendFeed here at ReadWriteWeb - you can see all our accounts there via this slideshow.

What are some of the most powerful queries you've thought up with the new FriendFeed search? We'd love to know.