Last night on Late Night, Will Ferrell shook his booty and his bob cut to his rendition of "I Got My Tight Pants On" — until an ugly (tight and white) rivalry erupted. "I'm the only one in this town that can wear tight pants," Ferrell threatened Jimmy Fallon. "Don't wake the snake! Hisssssss." Mollified, Ferrell later premiered the official trailer for The Campaign. Plus: A day after President Obama came out of the marriage equality closet, Conan spotlighted his own supportive gay staffers who rolled their eyes and silently dissed their boss for trying to win over gay viewers. Also: Girls' Zosia Mamet would fantasize about books during dates with douches; and Howie Mandel's vibrating workout belt went wild on the set of the Tonight Show. Watch our compilation to see what you missed.