Wall of Sound Soundbooth is worth trying out for their Twisted Mixes collection of stations. My favorite: Music to Die For, where somebody dies in every song. Hearing all those story-songs about heroic or tragic death strung together is a bizarre (and even depressing) experience.

For regular listening, I like Musical Confetti, randomly selected songs from every genre. Listening to the middle movement of a symphony then jumping straight to Funkytown amuses me endlessly.