My idea is a crazed sports fan. It's fun and really easy to do. All you need to do is find a shirt from you favorite sports team and then try to wear pants or shorts of their colors. You can even make pants that say the team's name and different things. Then you can paint you face or find temp. tattoos to put on. Get a big foam finger, a glove (if it's a baseball team), a team flag, and anything else you can think of.
It's also fun if you go with someone else and have them be the rival team.
For example, you go a Yankee fan and have a friend go as a Red Sox fan.
That makes for a lot of fun!
Thanks to Katie for this fun idea