Not up for this kind of activity on a school night? Then how about this oldie-but-goodie Chron article about SF's real-life fight club (though they wear mouthguards, so we question their hard-core cred)? Or follow local occasional essayist Matt Morin as he visits the same/another (we've never gotten a straight answer from him) SF fight club.
Image of the now single from/again reconciling with Jennifer Aniston Brad Pitt from Project Mayhem
(Ed note: SFist in no way guarantees the truth of either of the above referenced pieces, but encourages discussion on the potential validity thereof in the comments.)