[jonathanedwards]

Author here. This doc is just my personal curation of notable/interesting UIs for programming, as inspiration for my own research. Not attempting to be comprehensive, and being somewhat opinionated on the level of generality required to be called "programming". Thanks for all the links, I'll check them out.

[larsbrinkhoff]

Maybe look into colorForth, where the colors are not just syntax highlighting, but part of the language semantics.

[colinthompson]

Another relatively obscure but potentially interesting entry could be Field:

http://openendedgroup.com/field/OverviewBanners2.html