I'm starting to compile a list of various processor, and OS's they ran. An OS qualifies if it was general purpose, not a dedicated OS. CP/M, Apple DOS, etc qualify, ROM'ed things like vxWorks does not. Forth is a special category, and while it will be present in the list, doesn't need to be listed for every processor. I'm more interested in the smaller processors, and not getting into 68000, NS32000, etc. However, 8 bits is not a requirement. We can skip over x86 family however, as that list would be huge I plan to make this the basis of a webpage. Of course, if anyone knows of such a page already, feelk free to point me at it. I googled around, and had so many hits, I couldn't find reasonable search terms to cull it with. A starting point is: Z80: CP/M (and variants: MP/M, etc) TRS-DOS 6502: Apple DOS Commodore DOS (not sure of the name) 6800: Flex 1802: RCA COSMAC development system