Secunia Software Inspector provides a free online scan that provides a patch status for all supported applications on your system. It's a pretty long list of supported apps as well, including various versions of Adobe Reader, Flash, Firefox, Quicktime, AIM, iTunes, MSN Messenger, Windows, Thunderbird, Opera, RealPlayer, Skype, WinAmp, Yahoo Messenger, WinZip and ZoneAlarm.
Just click Start, let the scan run, and within moments Secunia Software Inspector provides a complete report of all that's wrong - or even right - with your system. A green checkmark beside a product name means that product is up-to-date. A red X means the product needs updating. And Secunia makes it doubly easy to update - providing links to the updates, step-by-step instructions, and details about the vulnerability.
Secunia Software Inspector is free, fast, and so intuitive to use there's simply no excuse for not keeping patches up to date.