Here’s a cool audio and video controller DIY using Arduino.
6-pack is an open-ended, highly customisable, and ultra-portable physical controller based on the Arduino board. 6-pack is an Arduino shield consisting of 6 linear potentiometer sliders that can be assigned to different variables in the user’s preferred software. It can be used to control a wide array of audio/video applications, from software synthesizers to HDJ systems. All, with a minimal footprint (3,5″ x 2,5″) and on the cheap (just a fraction of the cost of an equivalent MIDI interface). The project is open source. See below for schematics and source code.