since the demonstration and demo of BadUSB devices, which take over your computer unnoticed by coming as USB thumbdrive with internal USB keyboard, I wondered if it isn't quite easy to fix this potential threat for USR users: Adding an option that every time a USB keyboard is detected a confirmation dialog requires the user to allow this device to be enabled!
I just noticed that the quite famous USB Drive Letter Manager (from Uwe Sieber) added such a confirmation for USB keyboards to his program in the latest version, as protection from BadUSB devices.
This looks like an easy, simple and efficient way of adding substantial value to USR. You could even use this in advertising (protect yourself from BadUSB devices...).
(Or maybe this is possible already now and I missed how to do it?)