Nice game from Google

http://images.google.com/imagelabeler/

The idea described here (long lecture):
http://video.google.com/videoplay?docid=-8246463980976635143

What is missing: ranking of players and ability to couple with players of the same rank and age.
Sorting of players by expertises and specific areas of knowledge (science, sport, cinema, art, etc.).

The first iteration should help to attribute the pictures to areas/categories. After that it can be given to experts in those areas.

via dimrub