I recently reviewed the November OUCH newsletter for SANS. Bill Wyman put together an extensive list of commonly installed software products (and the patch sites for each). I thought it would be helpful to share this with readers. This is used with permission. If you do not subscribe to the SANS OUCH newsletter, I encourage you to do so. Yes, I am a reviewer. Here are the links to patches for these commonly encountered systems.
Windows: http://update.microsoft.com and http://www.microsoft.com/security/updates/bulletins/200910.aspx
OS X: http://support.apple.com/kb/HT1338
Acrobat Reader: http://www.adobe.com/downloads/updates/
Adobe Flash Player: http://get.adobe.com/flashplayer/
Google Chrome: http://googlechromeupdate.com/updates.html
Microsoft Security Essentials: http://www.microsoft.com/Security_Essentials/
I would appreciate comments as to how helpful this list is to you.