I never knew this was released since September 2006, so pardon me for being late.
http://images.google.com/imagelabeler/
You are paired against somebody who is using Image Labeler (randomly), and your pair has ninety (90) seconds to label as many pictures as you can. When a label you and your pair entered will match, the image is then labeled with that label, and you move on to the next image. You earn points and can get to accumulate them if you are logged in to Google Image Labeler (needs a Gmail account subscription). The quicker you get to label an image, the more points you earn.
Just head on out to the link to know more. I swear it took up a lot of my time, while waiting for a torrent to finish downloading.
P.S. and while we're at it, how about we post screenshots of the highest points that we got? I got 900, but didn't get the screenshot.
Hope you get to do better.