I&m a huge fan of single board computers, especially if they&re small enough to swallow.
That 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 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 definitely not a fully fledged computer & there are limited I/O options, obviously & but it a cute little tool for those who want to do a little open source computing.One problem It 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.