I'd like to add my 2cents. I've been programming since 1973 on many different platforms, and in terms of versatility vs. size, I'd go with the dBase language and platform (variants: xbase, clipper, foxpro). With 64K of memory, once could build full featured, screen oriented database programs, of pretty much any type.

Full accounting systems could be programmed to fit on a 1/2 meg floppy. Amazing. I would love to see it on the ITT (as I'm sure a bunch of other 40+ year old programmers).