The Teensy++ uses a AT90USB1286 and they have something called Teensyduino software add-on for Arduino Teensyduino - Add-on for Arduino IDE to use Teensy USB development board maybe this will bend to your will.
The Teensy++ uses a AT90USB1286 and they have something called Teensyduino software add-on for Arduino Teensyduino - Add-on for Arduino IDE to use Teensy USB development board maybe this will bend to your will.