You must have The Feerrott access to do this.
In The Feerrott there is a quest you can pick up, chances are you heard about it. The quest starter is under a small stone that you pick up, and is called a Tattered Robe. Location = p90 p304, behind a tree (this stone is tiny, keep your eye out for it)
Now, this quest respawns every 1-2 minutes, and you can stack this item in your inventory.
As you will know there is a merchant in The Feerrott, East of the docks. This merchant ( as far as i know ) gives the best prices, buying and selling.
This merchant will buy each Tattered Robe for 38s57c each...which is around 7g per stack.
You can get 1 stack in around 40 minutes.
You can get a basic script recorder off the net, in a google search. Which means you can run this while A.F.K.
I would imagine they will be changing the respawn times with this quest soon, so take advantage while you can. This is alot faster than any crafting exploit i have seen, and you don't even need to be at your computer to do it...