Audio Jack Key Board

thingiverse

I print this as a Christmas gift for my brother-in-law. All you need is five audio jacks with 6.35mm plugs. I purchased mine on eBay for €5 in packs of ten. I used the Amplify font from dafont.com. At the back, there's a secret compartment for storing keys that should remain hidden. You can use it with strong magnets that are 10mm in diameter and no taller than 3mm.