This post had a great tip for saving gold when you get to your 10g cap. Most items sell back to vendors for 25% of their cost. Now, you could go buy a 10g bag and resell it for 2.5g, but the problem is, they don’t stack, so each stack is worth only 2.5g. Walnut Stock costs 5g and sells for 1.25g, but stacks in piles of 10, so each stack is worth 12.5g.
Eternium Thread is another pretty good option. It stacks to 20 so you’re getting 15g per stack. Pretty nifty tip, just make sure you buy them from a vendor you’re Exalted with for the 20% purchase discount.
On a slight side-note, if your aim is to stockpile tons of cash, Goldenscale Vendorfish are the way to go. Instead of trying to avoid the 10g cap by converting gold into goods with the first two items, you’re just farming these for cash. They stack in quantities of 20 and are 6g a pop…for a whopping 120g per stack.