Hum, whistle, sing
How often have you been in a situation where you heard a tune on the radio, but did not catch the title nor the artist? Still, parts of the song are in your brain and you keep on humming, whistling, singing the same segment over and over.
Looks like somebody is working on a solution. midomi allows you to record a small segment (if your computer has a microphone attached) and they use it to identify the song that matches the segment best.

I’m not a singer, nor a hummer (ho ho), but the three samples I recorded were identified correctly. Nice job. (via waxy.org).
This is very cool!! Thanks for sharing. I will have to try it out.