Sargon II Chess for VIC-20 disassembly and relocation

FuzixOS: Because Small Is Beautiful

UNZIP and ZIP for CP/M Z80

Doom port for DOS, optimized to be as fast as possible!

The Open SIMH simulators package

The development kit for over a hundred z80 family machines - c compiler, assembler, linker, libraries.

CP/M system sources for the "Quorum", one of Russian clones of ZX Spectrum

Sharp MZ-80K programs

MAME

The Computer History Simulation Project