Like JZero said, IRC viruses have been around forever. If you all all incoming DCC's and you go and run them, you'll have a problem.
<< some servers do an intensive scan on your connection to see if you have certain ports open, ports known to be associated with said virus'. Correct me if I'm wrong... >>
Naw, you're right. One time I got a message telling me I had netbus on my system (stupid roommates). It's a super lame worm, but at least they told me about it 🙂