Prototype coming soon
So I'm pretty close to having a rough prototype working. This will use an Arduino Nano, PowerBoost 500 Basic, CardKB keyboard, SPI OLED screen, piezo buzzer and 2xAAA batteries. Hoping to get that all soldered together and working in the tin this week. My idea of using mini breadboards isn't feasible due to the size constraints of the Altoids tin.
That then begs the question: do I encourage people to build the same thing from all those modules? Or do I create a custom PCB using an ATMega 328P chip and make a single-board version to replace the Nano and PowerBoost?
3D printed bezel
My cousin has very kindly offered to design and build a 3D printed bezel to mount the OLED screen nicely in the top of the tin. Once finalised, we will make the files for that available here.
Thanks to everyone who has commented so far in the discussion section below. Lots of nice comments and suggestions. Some people seem to want this computer to do more. For that, I'd recommend searching hackaday.io for 'pocket computer' as there are lots of much more capable computers with SD card support, networking, better screens etc. But that's not what I'm going for here. I want a text-based 8 bit system that runs BASIC for a minimal cost. No frills. Maybe the frills will come with the eMBee TWO ;-)
Another commenter suggested I build my own keyboard. That's a possibility in the future (especially to make it feel nicer than the hard feel of the CardKB keyboard)