Andy Hauge Ron Edwards’ Trollbabe is from 2002, and its cited among the influences in AW (fronts are based on Trollbabe’s stakes). It’s the first example that i can recall of a game without any kind of “murk” in the rules, no part of the game is not covered by rules (you never ever need “rulings”), and all the rules are about player to player interaction (with the GM being a player).  i consider it one of the most important rpg designs ever.
And it does the “what does a game look like that lays those rules bare and makes them explicit?” bit much better than AW (IMHO) and almost ten years earlier.