I know the N900 is expensive for a cellphone, but for an autopilot, its not that bad.

I built a UAV in 2001 using an off-the-shelf autopilot that cost $5,000. For that price, the autopilot did not include a battery, GPS, or modem.

I would love to see an N900-controlled UAV!

Actually, I would really love to see someone make a USB servo controller for the N900.