Fibbex, a member of the BitFixGaming boards, made this sophisticated and precisely constructed guitar that looks just like a scaled up Nintendo Game Boy. It's completely functional in both modes, releasing impressive sounds and offering playable classic Nintendo games.
A Raspberry Pi microcontroller runs the emulator. The A and B buttons impressively serve double duty as gaming buttons and volume and tone dials for the guitar. You can see more build photos and descriptions here.
-via Technabob