WeFollow is a simple site that lists top Twitter users by tags.
Simple tweet @wefollow with the top three tags you'd like to be associated with.
Categories listed on the front page include news, celebrities, sports, and politics. You can also search by tags.
This site was created by Digg founder Kevin Rose. He says it's still buggy. I think it's a cool idea, and I want to see it take off once users start adding themselves to his database.