Here is another must have item you should support:
Allows control of those awesome Dynamixel servos. These servos have a micro that allows for reading back current, ramp speed profiles, temp shut down, servo daisy chaining, etc. The device is also made by the servo manufacturer.
The USB Dynamixel has an RS232, RS-485 and TTL interface for controlling all of the different Dynamixel servos. This device uses an FTDI chip and shows up as a comport to the PC. They also have an SDK.