I am not sure how long it has been removed from the Internet, but Symantec removed their free online virus scan utility.
Trend Micro, the makers of PC-cillin Internet Security, have a free online virus scan utility that can help you in case of an emergency. They call it HouseCall. You simply download an ActiveX Control and it will scan your PC for any viruses. Check it out here.
For a long-term solution, however, you don't want to rely on these free online virus scan utilities. You may want to check out PC-cillin Internet Security 2005. I haven't used it, but in various reviews it appears to be an excellent product and a lot less of a performance hog than Norton.