Secunia checks your PC for security vulnerabilities
Secunia Personal Security Inspector is a FREE program that scans your PC and reports programs you need to update because of security issues.
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Secunia is a respected security service provider that tracks vulnerabilities in more than 20,000 applications and operating systems.
The Secunia Personal Security Inspector Windows application scans your computer and lists insecure programs, information about vulnerabilities and links to the patches. In most cases, Secunia provides direct links to the latest updates, so they are easy to download and install.
On my XP laptop, Secunia reported seven down rev mainstream programs that need security updates.
This is Very Good Stuff. Just do it.
[via Google Operating System Blog]
http://googlesystem.blogspot.com/2009/01/update-vulnerable-programs-from-your.html