[Jerry Feldman]
As you and others have mentioned, if you practive "safe computing" you should not have a problem.
Recent events have shown that the only way to safe computing is to forever forbid removable media and any kind of network connections. :-) For a little while, I'm getting 5000 unwelcome messages per day on average, either trying to infect my systems, or wrongly warn me that I sent viruses, because my name is being spoofed as the `From' header in messages originating far from here, and widely broadcasted away from here. Likely, my name was found on the disks of numerous remote, infected systems. My various filters clean out about 99.85% of the clutter, still, enough goes within the cracks to be slightly annoying as a user, and surely annoying when considering the network bandwidth taken by this overall noise, and for which we have to pay. (Europeans might be paying more than we do here...) Most people would say that I practice computing in quite safe ways. :-)
The bottom line is that no system is immune to worms or viruses.
Systems may be quite bothered with worms and viruses, even when immune. -- François Pinard http://www.iro.umontreal.ca/~pinard