This might be unusual to say, but when I first listened to ? by Outkast I immediately thought there was a GD level that used it. I mean it makes sense, the song is less than 90 seconds long, I feel you could probably use the full song to make a pretty interesting level. Alas no one has but I feel sooner or later someone will do it- the song is just too much of a layup for people to pass up on.