Spaceman Spiff's Chording Keyboard Experiment (or SpiffChorder for short) is an experimental platform for creating a USB chording keyboard. A chording keyboard or Chorded keyboard is an input device where characters can be typed by pressing multiple keys at the same time. A popular design is the 7-key chorder, where one key is used for each of the index finger, middle finger, ring finger and pinky, and 3 keys for the thumb. This can be used with either the left or right hand (or a chorder can be used for each hand, effectively doubling the typing speed).
SpiffChorder hardware is based on Atmel AVR ATmega168, using Objective Development's V-USB (a software-only implementation of a low-speed USB device).