Minion + Nobles

Considering that Minion costs 5 coins, and the Nobles costs 6 coins, it's a pretty expensive combo to get going.  But if you avoid buying anything other than like silvers to get enough money to pick up either of these cards, then you should be able to get a decent number of these cards in your deck.  There are different ways of using these two cards when you have them in the same hand:

1. If you have a crappy hand, then you can use your nobles to give you +2 Actions and then use your minion to discard your hand and pick up another 4 cards in the process of hurting your opponents.  Now you have two actions to use with these new 4 cards instead of one.
   
2. If you have a decent hand that gives you like 3 or 4 coins, you can play the Minion to give you +2 Coins, and then use the Nobles to give you +3 cards in hopes that it gives you more coin and you will get enough for a province.