Those lucky enough to get an invite to Diesel's huge party on Saturday know it's going to be a blast: M.I.A., N.E.R.D, and Joel + Benji Madden all in one big warehouse, in Brooklyn, with tons of fashion kids and a red carpet curated by Starworks (read: lots of famous people). But even the extravaganza that is a Diesel bash can't necessarily contain this rumor: That Britney Spears is one of the night's surprise performers. We heard it from an entertainment agent based in the city, and we're like, "Nooooo!" and they're like, "I don't believe it, either, but that's what the rumor is." So, you know, it could be like Kate Winslet for Vivienne Westwood - totally wrong. Or it could be like Sonic Youth for Marc Jacobs - totally happening. Fingers crossed, kids.