DeMillitarized Zone. It opens up a port on your router to the internet with no firewall. It makes it... naked. Yes, naked to intrusion by insidious and lusty viruses. Though your PS3 should be safe from THAT. For now. Also try speaking when chatting. Many people don't realize that you have to use vocal chords to have other people hear you. That tricked me for a while.
"The well-placed coin changes much - even itself." - Lao-Tse