Err.....i beg to differ.
Just because you don't surf warez sites or porn doensn't means you are less vunerable. as an example, i once connected to my brand new streamyx connection and got hit by LSASS exploit aka sasser(or was it blaster) immediately.
simple click on a link you friend send to you via Instant Messenger would infect you with worms and trojans. Or perhaps you would like to share a tumbdrive only to be hit by brontok...
all this anot surfing porn or warez sites, yet very nasty viruses, trojans and worms propagate in various ways.

If you value you data, get a good antivirus and don't curse that it cost 'x' amount of money. its your precious data we are talking about here.

regards...

Or in english hospital at the edge of the disk and 'NO' Norton is no way related to ESET. The guys at ESET will be fuming mad if you relate them to Norton or Symantec. They are independent non public company ie. Sdn Bhd type. ESET is a technically oriented company with the CEO of the company whom is also a technical person.