Just ask yourself:
Make a sarcastic comment and then wander off in search of someone interesting to talk with. Or a pretty girl.
Refuse to star in Ghostbusters 3?
Bill Murray will show up at your house party and start washing the dishes! http://www.oddballdaily.com/2011/07/08/9-things-you-probably-didnt-know-about-bill-murray/
Bill would dress up as a zombie
The blog so nice they named it twice. (And to be clear, it's mostly about the Mission.)