Michael Sobolak made a cool little DIY touch piano.
Michael made this cool little MIDI Controller by first etching his own PCB that he designed in Illustrator using printer toner transfer and copper etching solution. There’s a bit of tricky soldering to the TouchSense inputs on the bottom of the Teensy, but the rest of the soldering is pretty simple.
Abelton Live was used for the sound libraries for this project, but it should also work with Garage Band or other digital audio workstation (DAW).
Code for the project can be found on this Instructibles page.