Tomu is a fingernail-sized computer that is easy to swallow

I'm a huge fan of single board computers, especially if they're small enough to swallow. That's why I like the Tomu. This teeny-tiny ARM processor essentially interfaces with your computer via the USB port and contains two LEDs and two buttons. Once it's plugged in the little computer can simulate a hard drive or mouse, send MIDI data, and even blink quickly.

The Tomu runs the Silicon Labs Happy Gecko EFM32HG309 and can also act as a Universal 2nd Factor security token. It is completely open source and all the code is on their GitHub.

I bought one for $30 and messed with it for a few hours. The programs are very simple and you can load in various tools including a clever little mouse mover - maybe to simulate mouse usage for an app - and a little app that blinks the lights quickly. Otherwise you can use it to turn your USB hub into an on-off switch for your computer. It's definitely not a fully fledged computer - there are limited I/O options, obviously - but it's a cute little tool for those who want to do a little open source computing.

One problem? It's really, really small. I'd do more work on mine but I already lost it while I was clearing off a desk so I could see it better. So it goes.