Randomizing the modules used for various songs can provide some hilarious results, most often if one of the guys is placed in a role meant for one of the girls and watching them execute the same dance moves.
Almost avoided in the Diva Rooms in F 2nd as Len and Kaito have "Affection Up" events different from the girls, but that doesn't stop them practicing a very feminine walk complete with Hartman Hips from time to time during normal room events.
Several of the Item Events in F and F 2nd:
The Paper Fan, used to punish a taiyaki thief.
The Silk Hat, wherein the user has a 1-in-7 chance of pulling the desired object (flowers) from the hat. All 6 "failure" scenarios and their reaction are hilarious as they include Hachune Miku, Larval Rin, Tako Luka, and more.
The end of Summer Idol, after Miku and Rin decide to be a couple after realizing that if one finds a date the other will be alone.