Thought of a couple more that should have been pretty obvious:
1. 50 Ironworks:
a) wins on board with Great Hall, Island, and any other action card at $4 or less. (2 turn game ftw!)
b) loses on a board with no action cards under 5...(I think all 8 estates + gameover in 8 turns would give the game to Ironworks, but maybe not since the other player just needs a couple duchies to win against that...so maybe any board without alt. VPs under 4 would take the Ironworks player)
2. 50 Workshops
a) Wins with Gardens, Silk Road, and no +buy/gainers. Gardens will be worth at least provinces by the end, then the Gardens player can take some Silk Roads, which should be good enough for him. Without +buy, the other player should be unable to catch up.
b) loses like ironworks (no actions under 5) trivially. But it probably loses on pretty much any board without Gardens, I mean 10 turns of grabbing some under-$4 cards aren't gonna be able to beat much.
ooh, on the subject of Gainers, I'll bet Feast could work similarly.
(it can get all the duchies in 8 turns, but closing out the game in 26 turns isn't very impressive...so a decent mega-turn, like say native village Bridge could probably take it by buying out the provinces. On the other hand, just like for Workshops, Gardens makes it nearly unbeatable. (add in Duke and you've got a pretty sure thing I think)