There has been a lot of work in recent years toward making amateur level UAVs. This one is a tricopter, and is completely open source. They claim that it can fly for “under $100 in parts, not including the airframe”. Sounds like a very cool project. It splits the computational load between an onboard pic that handles rate damping, PWM of the servos, and sensor capture, and a ground station computer which creates an interface and runs the navigation. Nifty.