Well, the computer I'm typing on at the moment was just resurrected from the dead.
The flood in my family room had toasted it's motherboard.
Insurance bought me a new one, but a used motherboard was $40 off of Ebay.
Had to re-install Windows, after downloading, (for free!) off of Microsoft.com, an ISO of the install disk (which I did not have, and they were willing to sell me!).
Online activation worked like a charm.