The story
The Commodore 900, nicknamed the Z Machine, was Commodore's attempt at a serious multi-user business computer. Developed largely at Commodore's German operation in 1984, it used a 16-bit Zilog Z8001 processor and ran Coherent, a Unix-like operating system from Mark Williams Company. It was planned in two forms: a workstation with a high-resolution monochrome display, and a server for several terminals.
The 900 was cancelled in 1985. Commodore had just bought Amiga, and a second new architecture was more than it could afford. A small number of units had already been built and passed into private hands, and the machine is now a prized rarity.