If you check out your KoPs you'll find a small box from Texas Instruments containing an MSP430F5529 LaunchPad. We got these into every KoP for making awesome operator interfaces just like you want!
There is a utility that comes with the NI Update called "Gamepad Tool" which will program the LaunchPad to act as a USB HID gamepad. Add a few buttons, and the IO pins on the LaunchPad map directly to the gamepad functions. We also extended the USB HID interface to include indicator lights, and NI even added the functionality to the robot code so you can access them directly!
For more info on how to use the LaunchPad as a gamepad, check out the wiki page we set up here:
http://processors.wiki.ti.com/index....cs_Competition
If you have any questions, feel free to PM me, or email the support line on the wiki (it goes to me and a few other TI engineers) and we'll be happy to help.
Good luck!