A true legend has used an Arduino microcontroller, 128x64p display, and 300 mAh battery to create the world's smallest ThinkPad (and probably laptop). To top it all off, the ThinkTiny can play some classic games and is controlled by a TrackPoint-style nub.
https://www.notebookcheck.net/Man-creates-world-s-smallest-working-ThinkPad-complete-with-stunning-64p-OLED-display-TrackPoint-and-20Mhz-CPU.428311.0.html