This does include the Windows product key but also other serial numbers for applications like Nero, Office, VMWare and pretty much every other application.

Instead of searching for the keys in your e-mails, manuals and recipes you could use another approach. LicenseCrawler is a sweet little application that scans the Windows Registry for Windows product keys and other serial numbers and licenses.

The LicenseCrawler can discover application product keys and other serial numbers or licenses very quickly and supports all versions of Windows operating system from Windows 95 over Windows 7 to Windows Server 2008 R2 (64Bit). Learn more.