Essentially a round-trip business class ticket from the US to Asia.
Buy gift card with credit card -> Unload gift card back to credit card. Repeat. Send the same $5000 around in a circle (less fees). I'm simplifying of course.
Bluebird, a prepaid debit card from Amex and Walmart, has been one of the big methods for some time but I'm not sure if that one is still viable.
While I don't deny the possibility that you're right, if you're not involved in the community I'd consider it far more likely that people have already found the most effective manufactured spend techniques.
As an example, CC charge -> Amex GC w/ cashback from rewards site -> Visa GC w/ PIN -> ATM or money order to withdraw is a fairly "simple" MS chain. The convolutions that people have discovered past that get pretty byzantine. But even <1% adds up when you're churning 5 figures.
The lengths of some of the schemes are entertaining in their own right.
If you know a year-round supplier of $0 fee cards, let us know ;)