[ToddF]

If pins are your problem, the I2C interface is the solution. The best priced servo driver board I've found is sold by Adafruit. It costs $14.95, is only 1"x2.5" in size, and drives 16 servos. You could add up to 62 of them for a total of 992 PWM outputs. I'll probably end up using one of these, but right now I'm experimenting to see what I can do without adding any supporting electronics.

I haven't yet researched I2C boards for input signals, but I'm sure they are out there.