From the MAKE Flickr photo pool

Ludo_d built a custom MIDI touchpad controller using Arduino -

Started from a scavenged Cirque Glidepoint resistive touchpad (PS/2 compatible), 2×8 LCD (in 4 bit mode), two buttons and a serial Arduino board.
The buttons when pressed allow to set the Continuous Controller number by gliding the finger on the touchpad. Left for CC# linked to X and right for Y.
The LCD displays the value sent in MIDI. Some custom characters where coded into the CGRAM in order to have a sort of bar graph. The first line is for X and the second for Y.

– TouchPad Midi in use

Related:

Nintendo DS MIDI

The Kaossilator