I ported a framebuffer-based terminal emulator (
fbpad) to the Kobo eink devices (specifically the Kobo Aura ONE, but I think any Mark 6 device would work). The code is at
https://github.com/kisonecat/fbpad-eink but I'll try to package it a bit more nicely. The main application is that, with ssh and tmux, it is possible to use the kobo as an external display on sunny days.