http://www.zdnet.com/registry-hack-e...xp-7000029851/

Williams says that the hack, included just below, makes the system look like Windows Embedded POSReady 2009 which will continue to receive updated until April 9, 2019.
I have a bunch of windows XP VMs, and don't plan on ever moving them to a later version of windows. So this sounds like it could be promising. At least until msft figures out a way to block it.

Also, this may mean your machine gets updates that are not compatible with regular XP. So beware of the downside...