Remotely Enable/Disable A Thermostat

I wanted a way to remotely enable and disable my thermostat for turning the system on when returning from vacation, or turning it off when I realize I will not be home when originally planned.  It should save energy and increase our comfort.  The wiring itself was actually fairly easy.Here is a link to a post with pictures describing the project:http://www.thomaswlewis.com/?p=567