I bootlegged a firewall, off limewire, norton firewal, its the only firewall available for macs os 9 or x that has good protection. Im not one to comment Symantic Products, but i think that Norton firewall is you're best bet and as far as free is concerned, boot leg it. use Limewire its the only mac p2p available at current and unlike the windows p2ps it doesent install garbage like spyware on you're system. And as far as you getting os X, i surely recommend it firewall or not OS X is very very stable and has 10 times more security issues fixed than the earlier os's.