Nootropic Design has modified the Arduino platform to offer not only TV-out, but also a built-in game controller, as well as support for external controllers (including Bluetooth-based Wiimotes).

Modder TommyB has created a DIY Steam Controller 2 that splits into two, created using parts from the handheld gaming PC and a 3D printer.

The digital fabrication boom has driven much of this work, most notably 3D printing and laser cutting. And most Alt Ctrl games typically piggyback on interface prototype platforms like Arduino or ...