I am seeking a program to make an I2C to PWM converter, for use with the AR Drone. I have attached a PWM converter program that had been doing this for the Mikrokopter, although it looks like it was only doing this on one channel (did he have four Arduinos for the four motors then?). So basically, if you can have this read the I2C stream or four I2C streams (I don't know if all the data is on one wire, or if you'd have to connect to all four wires to get each one's I2C data) then convert and output to four PWM's, then we're set. There's alot more detail about this in my other thread where I was trying to do this myself, but I've given up on trying to dive in head first on learning I2C and Arduino. I just have too much else going on and could likely throw money at this much more effectively than I could throw time at this.
So without further ado, here's the thread I wrote on here about this all in detail: http://arduino.cc/forum/index.php/topic,145610.0.html
Here is a link with a bunch of info about the AR Drone motor controllers: http://blog.perquin.com/blog/ardrone-motor-controller/
Here is a thread on the AR Drone Flyers forum I've also had many discussions on: http://www.ardrone-flyers.com/forum/viewtopic.php?f=8&t=4529