WinKeyFinder - · View Windows XP CD Key · Change Windows XP CD Key · View Windows Vista 32bit Edition CD Key · View MS Office 2007 CD Key · View/Change XP Key · View/Change MS office Key · View Win98 Key · view Win2000 Key · View .Net Key · View Windows2003 Key
Magic Jelly Bean Keyfinder works on Windows 95, 98, ME, 2000, XP, Vista, Server 2003, Server 2008, Office XP, Office 2003, and Office 2007 family of products.
and while you're at it, backup your XP activation files, AFAIK the latest WinKeyFinder features this option, if not, here'a a tutorial.