ZZT-OOP! Oh, the nostalgia. That was awesome. Well, not the language. Not the IDE. But the whole idea of a game having a built-in programming language. Was it the first of its kind? (Then again, in 1991, I don't suppose it was.)
JFYI, FORTH is now usually written Forth. (Like LISP is now normally written Lisp.)
(I tried to pick different PLs than russ if I could think of one, though I admit I didn't know of Yorick or Z++)