From: Richard <legalize at xmission.com> Google for AT&T 5620 and/or AT&T BLIT. The 730 is a descendant. They can be regular dumb terminals or "layers" terminals, which is a really rather interesting, pre-XTerminal remote windowing system worked on by, among other luminaries, Rob Pike. As I recall, they came out with an X cartridge for the 730 since layers never caught on. I only saw NCR rebadged X Terminals during my time at AT&T, so I assume the X cartridge didn't catch on either, even internally. Don't think many of them ever made it out of AT&T...at least I've never seen one in the wild.