i have a fairly expensive rig and i was wondering if i need to take any form of security to the event it a large event and i would just like to know if im being paranoid
(assuming you're on Windows 7) When you connect to the new network just make sure it's set as a public network rather than a home or work network. Other than that there shouldn't be any extra security precautions you should take. At least, as far as I know.
And just lock your computer if you leave it so no one can go on it.