‘Draw It Yourself’ is a MIDI controller created by Dani Sanz which uses conductive ink as push-buttons. It is based on Arduino Uno and uses a capacitive sensor to determine whether the drawn buttons are being touched or not:

This was my second semester project for the Interactive Music Systems Design Course (CDSIM) at the Music Technology Group (MTG) at University Pompeu Fabra of Barcelona. I presented this project at Sonar+D, part of the Sonar festival of Barcelona, held between June 12th and 14th 2014.

It can be used for multiple applications, not only for music! You can download the Fritzing  and make it yourself on the Instructable and see it in action with this video: