I don't know if this is a thing, but I've now played two games where this ended up working for me. Here's the idea:
Use Counterfeit to trash out the coppers in your deck (you don't need to get them all, just light trashing will help you line up your Madmans for later), Hermit to trash out Estates (and maybe Curses too). Use Hermits to gain more Hermits and Silvers. You can still use Counterfeits to trash coppers on turns where you don't buy anything to get Madmans.
Get 3/4 Madmans, 3/4 Counterfeits, a bunch of Silvers (10 maybe? Maybe a Gold or two?) and wait until the time is right, NV/Bridge style. Then, draw your deck with your Madmans and play a bunch of Counterfeits, trashing all your good treasures for lots of money and lots of buys, and buy a bunch of green to end the game.
This is not refined or fully tested. Perhaps I can do some more research on this. Just wanted to get it out there.
EDIT (with numbers!):
As many Silvers as you end up getting, it seems you want to buy Counterfeit over gold, since on your megaturn, you end up with more buys but the same amount of money.
If you have only Silvers and Counterfeits, let's say you get 4 Counterfeits. In order to get $42 (probably a safe amount to end the game on, since you can get 30 points that way pretty safely) you need 14 Silvers. Yeach.
What if you got 5 Counterfeits? Now you only need 12 Silvers. Each additional Counterfeit you gain reduces the number of Silvers you need by two (so do Golds, if the Counterfeits run out, as long as you have enough Buys -- 5 Counterfeits gets you 10 Buys which should be enough). You can increase your chances of lining up Madmans this way, or also by just getting more Madmans.
So I think the opening here is Hermit/Silver (or Counterfeit/nothing on 5/2?) just to try and get an early Counterfeit or two. Aim for at least 4 Counterfeits and Madmans, keep careful track of how much money is in your deck and continue to build until you can megaturn and end the game.
I wonder if this is fast enough, or how fast this is...
