Bench demo of UAV Dev Board (UDB) showing a proof of concept of how to fly an R/C airplane over the internet using a cell phone and laptop. I have since flown this and the code is available, see update below.
Links:
Android WiFi Tether: http://code.google.com/p/android-wifi-tether/ (but any WiFi tether App will work. These days I use the built in Google feature)
UDB: https://code.google.com/p/gentlenav/source/checkout
HappyKillmore's GCS: http://code.google.com/p/happykillmore-gcs/
UPDATE: This video is quite old and I have since combined the PIC32 code running the IP stack into the UAV Dev Board (UDB) and flown it with UDP and it works GREAT! The firmware source code and the GUI App can be downloaded from the gentlenav source code repository. The App is currently called "FlyByWire App" but may get changed to something more accurate. The App is in /trunk and the IP stack is in branches/MatrixPilot_IP and maybe by the time you read this it will have been ported to trunk also. The FlyByWire App is written in C# usinf VS2k8 and can work over TCPs, TCPc, UDPs, UDPc and Serial. It is much fancier now than in the video there. For the cell phone thing I suggest UDPclient.