I would like to build a RF transmitter/controller for my garage. When my vehicle gets within 25', I'd like for a computer to trigger a physical relay to open my garage door. you know, like Batman.
I like Python, so I'm hoping I can use it here.
Have you looked into getting a basic arduino?  It sounds like you should pick up a cheap one at Radio Shack and get the RF devices to trigger your garage door opener remotely.  With the hardware, you can easily talk to it via python (though it'd be easy enough to just do with the Arduino language).
Can I use Python to interact with an RF transmitter/controller?