This looks interesting. There are a fair number of USB stick computers on the market. the Tomu is different because it id so small it fits entirely inside your computer’s USB port.
The board is based around Silicon Labs “Happy Gecko” EFM32HG309 Arm Cortex-M0+ microcontroller. It was inspired by the YubiKey 4 Nano. The project is entirely open source with the hardware under the CC BY-SA 4.0 with documentation available on GitHub.