Virus Management:   Free Online Virus Scan by Microsoft

The Microsoft Windows Live Safety Center http://safety.live.com/site/en-US/default.htm   is an online free service that scans your PC for viruses, performs disk clean-up, disk defragments your hard disk and check for open ports.  The service may say you have a virus when it is just a cookie or a java script, however for free, it's great for the price