Too late for it to, er, still be in existence, i stumbled upon Cueup’s “Colossal Cue Adventure”. But to my surprise, I found that it was still playable through the Wayback Machine: web.archive.org/web/201301210815 … cueup.com/
Nominally a text adventure game, it is a framework supporting several programming problems, which someone has apparently spoiled over at gist.github.com/builtinnya/5011449
(Programmer-y enough that with what amounts to a walkthrough there, I was still unable to make heads or tails of the actual game.)
Thought it might be worth documenting over at the IFWiki, IFDB etc., but to do so usefully would require a deeper understanding of the play experience than I am able to bring to the table.