There are also a couple of quests scattered around that require engineering items. Don't remember if the items are by themselves or required by another profession to build something.
For instance how the old un'goro quest for A-Me required a Mithril Casing (quest was removed). Usually when doing these quests (for loremaster) players won't be able to find these things on the AH and would be willing to spend a few hundred gold just to get it done. Fill that demand and you can make some nice gold.
Cogwheels, dragonlings, pets and the mounts. You would be suprised at how many people don't want to craft that flying mount and will purchase it. When I played with eng a bit I used to sell tons of those flying mounts, would cost me next to nothing and I would make like a 60% profit from it. Crazy stuff.
As others have said, there will be a new mount coming in 5.4, this will be HUGE for gold-making with engineering. Try to save up some living steel (will take 30 to make) because when 5.4 hits the price of living steel will SKY ROCKET! I don't even have eng and I will be purchasing a bunch of living steel for the upcoming patch.
Originally Posted by Vampz
inb4 "flying is a major part of the reason I have fun in wow!" Buy a fucking flight sim then