Buy an ESC, fit it into a little box with lots of open ended wires coming through the side of the box, fill the box with opaque potting compound. Use the arduino to provide a speed control signal to the ESC. Tie the open ended wires to as many spare I/O terminals on your arduino as you can and call the box a signal conditioner, with a 'secret' piece of eprom software built in.
QED, motor control "using" an arduino.
