cowbaal, in theory you should have a virus scanner and a full security setup and all updates if you even use a computer. The problem with this theory is it's impraticle. Think about all the resources you are wasting simply to run these programs. If you jump on the internet to check your email once every 3 months and you don't accept emails from sadaam, osama and kevin. You should be good. Of course you can get a virus from a friend that doesn't know they are sending it to you. But, in all honesty most viruses I have come across aren't simply just to try to destroy your computer, they want info.

And if your on the internet for 10 seconds the time its gonna take that virus to install and gather all the information that it wants is going to exceed the time your on the internet. I am not suggesting that you run without one if you use your email or w/e periodically. But, if you have no use for the internet. Then there is no need. And cow. There is an old saying if someone touches your computer you're already screwed. By that time you are too late and your virus scanner isn't going to do much.