Race has come up a bit lately, so I thought I'd throw this out there. The whole site is great, but I thought this quiz was very cool, even though I flunked it horribly.
http://www.pbs.org/race/002_SortingPeople/002_00-home.htm
http://www.pbs.org/race/002_SortingPeople/002_00-home.htm
