One Armed Man's Set Analysis and Combo update 2: (This is mainly for combos with at least one of the cards posted from contest 12 to 18)
Mountain Pass, Salesman, Missionary, Flea Market or Silver Smelter + Production Village: Those cards reduce your hand size, Production Village fills it up. Flea Market especially because the Production Village pile might run out, causing acquired Flea Markets to be top-decked.
Mountain Pass, Missionary, Barge, and Pawn Shop are competing trashers. They are also competing with Copper-loving strategies. Barge and Pawn shop let you turn Estates to coppers to help Aqua Vitae.
Barge + Pawn Shop: With a Barge in play, Pawn Shopping to convert into coppers, you get the choice of trashing from your hand for each of the gained Coppers.
Flea Market + Canal: Supply Pile synergy? I am not sure.
Astrolabe + Tea House: You can set aside each Tea House as you buy them, putting a card back on top of your deck for incredibly unimpeded greening. With a rush, you can put an Astrolabe on your deck every time you use Tea House, making a greenless deck that is still worth lots of VP.
Carpenter has good friends now: Salesman, Soothsayer, Silver Smelter (get 2 on the same turn, they are weak without a high density of them in your deck), Barge, and Flea Market.
Carpenter + Mountain Pass, Salesman, and/or Missionary: With cost reducers, Carpenter acts as a virtual +Buy so that you can gain 5 or 6 cost cards, even provinces if you have a self-synergy engine going.
Silver Smelter + Flea Market: Flea Market requires a discard and Silver Smether makes a good target for it.
Barge + Production Village: You might not know that Barge works as a virtual Watchtower. If you are junked by an Ambassador, Curser, or Jester, you can trash out of your hand on opponent's turns.
Salesman + (Harbinger) or Amulet: When you are in the middle of a Salesman chain, you need a card that you can gain to bridge the gap between Salesman and Gold. For this set, you don't have a 5 cost village, so if you need a 5 cost card, there you go.
Counter: Astrolabe vs. Soothsayer: Even if you have gotten rid of most of your Coppers, on any turn you aren't greening you can discard Astrolabe to protect yourself from Curses.
Counter: Missionary vs. Soothsayer: You can discard a Missionary to gain nothing instead of a Curse.
Counter: Landfall vs. Tea House rush: If your opponent is rushing Tea Houses, then your Landfalls are non-terminal. Use the +Buy carefully, or you can expedite the piles ending your opponent wants.
Counter: Farmers' Market vs Garrison: Top deck some Victory cards and Curses to by-pass. This counter is the same as Farming Village vs Ghost Ship.
We need another source of +Actions. The self-synergizing cards need villages in order to work properly!