The ATMega 32U4 is an 8-bit AVR microcontroller featuring 32KB self-programming flash program memory, 2.5KB SRAM, 1KB EEPROM and a 12-channel 10-bit A/D-converter. It even has on-chip USB 2.0. You might recognize it from our Pro Micro development boards as well as the Arduino Leonardo. Project description, more information and ordering can be found at https://www.sparkfun.com/products/11117 Datasheet: http://dlnmh9ip6v2uc.cloudfront.net/datasheets/Dev/Arduino/Boards/ATMega32U4.pdf Driver: http://dlnmh9ip6v2uc.cloudfront.net/datasheets/Dev/AVR/LUFA CDC Bootloader.inf Github Page: https://github.com/SFE-Jordan/Sparkfun_32U4_Breakout_Board LUFA Project: http://www.fourwalledcubicle.com/LUFA.php Product Video: http://youtu.be/3fw7jIcitYc?t=1m23s