Stars
An Arduino based "tape emulator" for the Kosmos CP1 experimental computer kit that reads from and writes to microSD cards.
Ready-to-run qemu disk images of Native Oberon 2.3.6 and Native Oberon 2003-01-05 (2.3.7Alpha?)
An emulator for the Kosmos CP1 "Computer Praxis" experimental kit that was sold in german-speaking Europe in the early 80s of the last century.
A free and strong UCI chess engine
Theorema: A System for Automated Reasoning (Theorem Proving) and Automated Theory Exploration based on Mathematica
The TI-Nspire calculator extension for native applications