My work computer actually has McAfee on it, which I've disabled through the registry. Don't like how slow it makes my computer.
Education, people! It's better than buying useless feel-good software.
A cold virus's best strategy, for example, is to keep you awake coughing so your immune system is weak, make you sneeze and cough and have a runny nose so you spread germs, etc. But it shouldn't kill you, especially not before you pass it on. I've heard (did I read it in Guns, Germs and Steel?) that syphillis used to be more deadly, but that it got milder as an adaptive strategy.
Likewise, computer viruses probably have a pain threshold they shouldn't pass. If they can do their masters' bidding without hacking you off so bad that you format the computer, they'll be more successful.
Possibly unwarranted conclusion: computer viruses are now widespread precisely because they're Not That Bad.
So, are they worse than antivirus software? A lot of non-geeks may be asking themselves that question today. "Dang, we got a virus one time, but it didn't keep the computer from BOOTing!"
McAfee has just demonstrated a computer autoimmune disease.
My goodness, what a fascinating idea. (And a search suggests the you are the first person in all of history to think of that.)
When will the biological parallels end? Will we someday get viral transmission of OS code snippets from one machine to another, leading to improved OSs? The mind boggles ....