A fun little arduino pro micro based rotary encoder thingie, which connects as a HID mouse and has a scroll wheel and also changes colour.
The HSV->RGB function, which is probably the most interesting thing in this code, was copied (with permission) from bertho's wonderful implementation in OSAA's IKEA sign
The encoder is from sparkfun
This code is released under GPLv3: http://www.gnu.org/copyleft/gpl.html
The Encoder library is from here