Hey Vinny...you asked a serious question...and you've gotten mostly serious (one smartass) replies. I had a pretty rotten "auto play worm" a few years back on os9 which was ugly. Ran Norton antivirus and cleared it up with no further probs. Have one PC and 7 macs....I choose to keep Norton on the Macs and PC...but, like the others have said...macs are pretty much virus-free. The norton on the PC works overtime....it's absolutely sickening at the crap that attacks pc's. Thank God we're mac-based. If I were you...I'd put norton or virex on my powerbook....download definitions every 6 to 8 weeks...just to be on the safe side...and SMILE a lot! Good luck. I have a powerbook and it rocks. cheers...brick