Catboard Keyboard 😸 ⌨
the catboard is one of the early DIY keyboard, around 2013.
Key count: 60.
catboard home at http://catboard.klava.org/
https://github.com/ibnteo/catboard
Pre-Assembled Catboard
Apparently, some Chinese company is selling it on taobao.
They sell several versions. One is finished product, and they also sell the full kit.
It appears, the full-kit may have electronic problems, where the USB connector is reversed and the chip gets very hot. i don't fully understand the Japanese.
Alternatives
In comparsion to other super compact keyboards, i think i like catboard better.