FEMU - Wi-Fi and Bluetooth enabled MicroPython board, fits in a USB port!
FEMU (Femto's ESP32 ModUle) is my take on the TOMU/FOMU form factor. This design is 100% open source, and runs MicroPython! It is Wi-Fi and Bluetooth 4.2 enabled. It also has an RGB LED, a DAC pin, a GND (ground) pin, and a 3.3V pin!
It fits in a USB port.