AVR Contest 2006 on Circuit Cellar
The eligible devices from the AVR stable are: AT90CAN32/128, AT90PWM2/3, ATmega16/32/48/88/168/169, and ATtiny13/25/45/85.
Total prize money is USD 15000.
As part of the competition, participants, after registration, can request a free Butterfly evaluation kit and chip samples. The sample chips will be two numbers of ATtiny13, ATmega16, ATmega88, AT90CAN128, or AT90PWM3 only.
At this point I not sure, if one can make use of the Butterfly itself as part of the project. I have asked the contest administrator and awaiting a response.