I would happily consider making an SD card that implemented an X-10 compatible RF transmitter. Given as Griffin is a real company quite familiar with FCC approval that aspect doesn't bother me at all (FYI, FCC cert cost $5600 the last time I did it for one of our products). However, I have very little interest in reverse-engineering the protocol, so if someone can point me to a nice concise explaination it might get this project going. RF engineers who have already built their own hobby transmitter and are willing to spill their guts are encouraged to get a hold of me. :)

--Don