A thought that occurred to me recently: is it possible to use the spare parts that a lot of RC shops sell, or maybe a semi-dismantled RC transmitter handset, to make your own transmitter? As in, build something from an Arduino/BeagleBoard/Gumstix/custom PCB/whatever and then connect it to the transmitting part of the RC handset, at any level - either some handset that will accept some kind of data input and send it for you, or right down on the raw electronics end, soldering bits together.
Basically, I'd like to get some computer assistance into the loop, using telemetry data to allow the system to act like fly-by-wire software, tweaking and moderating the control inputs to stop the pilot from departing from a safe flight envelope. If done right, it should make the aircraft controllable with just one two-axis thumbstick, trading separate controls for all the surfaces for basic up-down/left-right and a throttle slider. I was just wondering if it would be at all possible to build this into the actual handset (ignoring for a moment the issue of how the telemetry data would get to said handset) so that I could use the tried and tested transmission method, rather than having to fight past the latency and patchy signal issues of something like an XBee.
If not, then hey, back to the drawing board I guess. This is still early concept stages, so no great loss.