College football: University of South Carolina, mainly because Columbia is my home town. And I like cheering for the underdog (we always are). Notre Dame because I visited the campus once and it was beautiful. Plus a favorite aunt is a huge fan and I've always like Lou Holtz (he's at USC now).
NFL: Dallas, always been a Tom Landry fan.
MLB: Slightly more exciting than watching grass grow, but Atlanta is my team. My grandmother was a huge fan thus affecting my loyalty to them.
Moto GP: Gauloises Yamaha. Formerly Repsol Honda. Because Rossi does things on those bikes that sometimes defies logic.