I've decided that, now that I've got a leveling controller that works, it's time to cut the tether and move my controller code (in Python) over to an embedded controller that lives on the quad. I've currently got two pieces of hardware laying around that might do the job:
Gumstix Connex 400M BT:
SRV-1 Blackfin Camera + Radio/Motor module:
They're both pretty schweet:
Pro and Con:
No matter which I choose, I can see that there are going to be difficulties with porting my Python code from Windows to Linux, because I'll need the ctypes module in order to use the high-resolution sleep code that I grabbed from the web somewhere.