Tiny Arcade retro cabinets aren't just small enough to play from your desktop, they're small enough to play from the palm of your hand. If you have tiny hands. And the delicate, dextrous fingers of a child prodigy harpist. Full-color OLED screens and free games are nice and all, but I'm going to need some Operation tweezers and a fine-tip stylus to move the joystick and punch the buttons.
Tiny Arcade, available in build-your-own and preassembled models, is built around modular, Arduino-compatible platform TinyCircuits--itself no bigger than a quarter. The TinyCircuits click together like LEGOs and pair with an analog joystick and 2 push buttons, plus a built-in speaker for audio (and you can also use a Tiny Arcade to play videos at 30 FPS), Lithium battery, USB charging port, and microSD expansion slot. You don't need programming knowledge or special software to put together or play a Tiny Arcade, just an abiding love for the classics, and the precision of a surgeon.
Builds come with a few free games, and the open-source system hopes that community members will develop many more.
At printing, Tiny Arcades had completed a successful Kickstarter campaign and was in the process of shipping to backers. They were accepting further pre-orders through Backerkit, with sets shipping as they're completed.
May 2017 Update: TinyCircuits is up, running, and selling Tiny Arcades directly.