Here are some good ones:
Continuously talk for 3 minutes without stopping
Act like a gorilla for 1 minute
Go outside and sing "I'm A Little Teapot" with all the actions
Give a piggyback to the player on your right
Moonwalk across the room
For the rest of the game, randomly blurt out exclamations
The group picks a word, and you have to say it in every sentence for the next (insert time here)
Chat with our AI personalities