Seattle PI tech beat reporter and frequent news breaker John Cook is reporting that the math-heavy travel price prediction service Farecast has been bought by parties unknown for $75 million. The Seattle company has refused comment on the acquisition rumor.

Farecast uses extensive historical observation and algorithmic analysis to search for cheap flights in the US and then advise whether the price is likely to rise or fall in coming days.

The company has expanded to include international travel, analysis of the "fairness" of hotel prices and price guarantees or "lock-in" for a small fee. Farecast was founded by Oren Etzioni, the head of the University of Washington Computer Science Department’s Turing Center and the founder of search engine MetaCrawler. TechCrunch has covered the company's development extensively.

The company raised $20m and began development with a small army of computer scientists in 2003. It launched in 2006 and has quietly grown to become a favorite among tool-savvy travel searchers.

Cook doesn't have any information about who is believed to have bought the company but says that Expedia, with offices just down the road in Bellevue, Washington, is the most logical suspect.

Farecast seems like a technology that's been just waiting to be acquired since before it launched, it's almost a mystery that it's taken this long and that the price is as low as Cook says it is. After raising more than $20 million in venture capital, a 4X exit seems modest if the technology is as good as it seems to be. Maybe it's a real deal involving real technology and real cash money, though. The AdSense along the side of the site has just been proof of concept of course. A team like Farecast's is meant to focus on the science of prediction and get picked up by someone else who can sell ads.