Researchers based at Zhejiang University in China have produced a system for controlling a quad-rotor unmanned aerial vehicle with the mind. Dubbed "Flying Buddy 2", the system uses a standard, commercially-available Electroencephalogram (EEG) headset, a computer and a Parrot AR Drone. The computer processes the data received from the EEG and converts it into control commands which are beamed to the drone via a Wi-Fi connection. Judging by the video, the latency of the setup appears to be relatively low.
Looks like fun to me.