With $75 you can get yourself a Parrot A. R. Drone Quadricopter

Drone Quadricopters are not new but the The Parrot A. R. Drone Quadricopter is probably one of the first that can be controlled by an iPad, iPhone or iPod touch. It does not require the usual control handles that we use to rely on in the past. With your iPhone you can just tilt and touch and it will move in the direction you want it to. It comes with an autopilot feature that stabilizes it without you making any effort. You just have to remove your finger from your iPhone and the drone is on its own. We can't think of any drone cheaper than this one. Some of them can cost as much as a $1000. This is a good deal.