Although most viruses and malware are easy to avoid for the "informed user" the "naive user" is still a humongous target. I could NOT keep malware and viruses and unwanted Firefox toolbars off my kid's computer. I lectured them and told them how to avoid most of them (don't install things without asking me), took away their admin rights, etc. It did no good, the stuff kept appearing, even though we've tried both AVG and Norton. I think most of them are appearing because my daughter likes to Google Image search for cute puppy pictures. It makes me wonder if the malware distributing population has figured out kids are the best conduit to getting their apps on your computer. So now they're using Linux. Took them 10 minutes to figure out where everything was. Plus the machine is much faster without an antivirus running and checking everything they do.