Product Key Finder is a very small freeware app that finds many Windows product keys in your registry.
After a while you may be facing a situation where you need a product key for something you installed a while ago. This leads to hunting around for the original CD etc. This little gem will list out product keys for many Windows installed programs; most other key finders are limited to Microsoft products only and this one is a but more useful as it will find keys for about 200+ products.
Install this app, run it and you see this screen:
I’ve erased most of the key data I found, but you get the idea – very simple and quick solution.