Advice for a Defcon Virgin

"From a network perspective, assume that you are surrounded by hostiles.
These hostiles will be friendly. Assume they will attempt social engineering attacks on you when you talk with them. Be a scrooge when handing out information. It should be easy enough to chit-chat without giving out your full name, etc.
Social engineering may include beer. Beer is a wonderful way to get people to do things they wouldn't normally do - including giving out info.
This may sound strange, but do not drink any beverage that doesn't come from a well-known brand in a factory-sealed container...unless you like waking up with your underwear as a hat in a strange location.
If in doubt about what info to give, don't say it. Remember, people can now guess your social security number from just your birth date and city. A little info goes a long way for an attacker.
If you insist on taking a computer, consider the software installation on it to be disposable and/or compromised; just burn whatever contents you get to a CD/DVD when you get back, and nuke it from orbit. No point in bringing home little wormy-worms and bugs on your machine.
If you have to leave it in a room behind a locked door, assume you might not find it when you get back. Travel light and think ""mobile"" or ""nomadic"". Remember, they do demonstrations of how to pick locks..."