The Commodore Amiga. I used several Amigas productively long after their heyday, but I loved these machines and their OS. Way ahead of their time. Some people are still developing new versions of the workbench OS and newer hardware to run it on. However, the technology gap is now too big for any of it to catch up. Against my better judgement I’m still rooting for some of these products to succeed and be a viable alternative to Windows, Mac or Linux PCs.