Scan your computer's security and virus vulnerabilities over the web
PC Pitstop AntiVirus Center Virus Scan
PC Pitstop is recommended by PC World. It scans your computer for virus in just a few minutes.
Symantec Security Check
Symantec Security Check tells you if other people can enter your computer and hack it.
Shields UP! -- Internet Connection Security Analysis
Shields UP! also scans your computer to see if other people can take control of your machine.