How Do I Prevent Lan Party Theft?

DragonTHC writes "I'm thinking about hosting a lan party open to the public. I'm aiming for approximately 60 people to attend. I can handle all the logistics of operation. The only thing I can't wrap my head around is: how do I prevent theft at the lan party? Do I hire security guards? Do I need security cameras? I don't know the people who will attend, and I don't know if they're trustworthy enough to not steal other people's equipment. What do I do?"