The form factor is similar to the old Onion SBC, but more expensive and less capable. The Onion was $5, and included a proper serial interface, an SD card slot

The form factor is similar to the old Onion SBC, but more expensive and less capable. The Onion was $5, and included a proper serial interface, an SD card slot and wifi. It might have also had Bluetooth, but I'm not sure as this was seven years ago. It was a great little machine. Very promising to have an entire Linux machine the size and shape of a 6502. Alas, the company that made it put out a firmware update that made them act unpredictably, then another that ended up bricking machines. And at a cost of $5, there was no margin for customer support. The last time I looked into it, several years ago, the company appeared to be in pivot mode. There was a vibrant emerging market of tiny SBCs in the years before COVID. Now everything is Raspberry Pi and Arduino. If you can get one.