When was any? I find these sorts of things crumble in your hands, because as soon as you pick a candidate you find yourself thinking "but that was just a variant of such-and-such earlier idea."
I know what you mean - Smalltalk was Lisp + Simula and so on. Yet even if everything's a hybrid, some hybrids feel plainly derivative while others seem magically deep. In order to avoid tedious arguments about historical primacy, perhaps a better way to phrase the question is: what languages (or language ideas) feel most fundamental to people? I've given my list. What strikes me is how there isn't anything more recen…
Even more broadly, when was the last big idea in academia? Yes, they've mapped the human genome and all that, but that's just grunt work, not a big idea that lead to new fruitful research. I don't know a lot about the different disciplines, but it seems like math is running out of steam, so I've heard from a PhD student who switched to CS.