Even at 25 bucks the full version can be quite useful, I have used it multiple times in the past on a few different machines. Especially useful if you have a lot of "friends" who have you help with tech support...
Another piece of software is belarc advisor. Only thing to be careful with, you may get stuck calling microsoft. On some machines I've worked on, belarc advisor has shown a different key than what is on the casing, which is probably due to the manufacturer using a master image for many different machines.
wow... I didnt even realize Belarc advisor gave keys... sad that I paid for that other program when it's free... Thanks for that Ohiou