If you have a character with a Leatherworking skill of 485 and a character at level 84-85 (it does not need to be the same character), it is quite possible for this scheme to make you thousands of gold in the time it takes you to take three portals. How? First look at the following picture:
Anything jump out at you? For the uninitiated, Savage Leather Scraps are Skinned from lower-level Cataclysm mobs and have no function in of themselves. You can, however, combine five of them at a time into one piece of perfectly good Savage Leather at 425 Leatherworking. In the above picture, we can see that the prices for Savage Leather Scraps are not, in fact, anywhere close to matching their proportionally-priced counterparts. In other words, you can buy five Savage Leather Scraps for ~9.75g, right click them, and sell the result for 35g. I did just that in the opening days of the expansion and ended up with something stupendously large like 14 stacks of Savage Leather without having skinned a single mob.
It would be easy to stop there and be satisfied with our haul, but we can click a few more buttons and increase the profit potential by, oh, let's say a thousand times. With all of your 28% priced Savage Leather, you can combine them via a 485 Leatherworker into Heavy Savage Leather which increases it's value quite a bit already (none was selling at 1000g apiece however). With your Heavy Savage Leather neatly stacked in increments of 10, it is time to take the final plunge: Pristine Hide.
Much like Arctic Fur of the Wrath days, Pristine Hide is something that can be Skinned very rarely from level-appropiate mobs... or very commonly purchased from Misty Merriweather (Alliance) or Threm Blackscalp (Horde) out in Twilight Highlands by anyone with 10 pieces of Heavy Savage Leather to rub together. This was actually one of my favorite activities in Wrath, as you could easily come across cheap Borean Leather on the AH and after some Leatherworking alchemy turn around and start selling Leg Armor kits with a 60% margin. In any case, I had neglected this market for quite some time until there was an auspicious bidding war in /Trade that was establishing Pristine Hide's value in the neighborhood of 1850g.
Yeah, my jaw did the same thing.
Prices have dropped quite a bit since I wrote this article a few days ago, but the underlying scheme still works:
If Scraps x5 < Savage, then Buy.
If Savage x5 < Heavy Savage, then Convert.
If Heavy Savage x10 < Pristine, then Trade.