Get as many signatures as possible in 4 minutes on your "cast".
Paper bags. Markers.
Give all of your guests a marker, and have everyone at the party put a paper bag over their signing hand (arm). When the host/hostess says, "Go," then everyone in the room must obtain as many signatures as they can. It isn't as easy as it sounds though, because each person has to keep the paper bag on their signing hand (so they must sign with the opposite hand). At the end of 4 minutes, the person with the most signatures is the winner!