All, Figures I'd be out of town when this topic came up; I'd been waiting for a quiet moment to ask about them as well. I remember *lusting* for a digital group system just before dad bought a TRS-80 Model 1. (He was right, Tandy made systems for a lot longer than digital group did. :-() digital group chassis had a backplane bus which could accomodate processor cards carrying any of the 4 processor architectures mentioned by Sam (6502, 6800, 8080, and the super-powerful chip of the future Z-80). They offered a storage system using cassette tapes but recording to them digitally, not tone-encoded, which they called the phi-deck (I think). They sold a separate cabinet which would hold up to 4 of those, for a pretty large (for those days) total storage - over a megabyte, if I recall correctly. They sold a fair selection of software. I recall OASIS (sic?) as the name of one of the operating systems, and OPUS-1 and OPUS-2 as the names of two levels of a programming language (I think). I trashed my promotional literature describing all of this years and years ago, once we decided to go the TRS-80 route. Sigh. If anyone can amplify or correct any of this, or better yet has a working system, I'd love to hear more about it. Oh yes, there was a picture of one of the cabinets on the cover of Byte magazine just before they went out of business. Along with many other systems, suspended in space around a shattering crystal goblet with the Title "Breaking the Sound Barrier". The cover story was about computers with sound-generation capability. This would be maybe 1-2 years after the introduction of the Z-80, I'd guess, but don't remember better than that. More and better information, anyone? - Mark