Best B-side?

[SkeeK]

What do you guys say is the best underworld b-side? i'm thinking in rock terms not dance terms.. like a track that isn't on any album and isn't a remix (though.. given some of underworld's remixes we can be a little lax here). for the heck of it i'm considering the best of an album.. so it this will be about the exposition of rare gems (riverrun counts as albums, too i guess)