I just got my MBP a week ago and of course I've heard all the stuff about how Macs never get viruses and whatnot, but I'm sure this is just because there are more PCs out there so hackers target PCs more often. If a Mac gets targeted and you don't have anti-virus, you're basically screwed. My university offers free anti-virus for Mac and PC, but will it slow down my MBP if it's always running in the background (I have 4 GB RAM)? Do any of you guys have anti-virus software or think it might one day come in handy?