Im sure everyone is aware of how big twinks are these days. Anyway, I've found that farming twink gear and selling in the AH is a VERY profitable source of income and it's easy due to game mechanics. Only thing you really need is a lvl 60 character...rogues, warriors, and mages seem to be the easiest.
You simply run BFD, SFK, SM (except cath), and RFK...KILL EVERY MOB IN THE INSTANCE. The BoE blues that drop sell for more than most lvl 55-60 blues on my server. On average I make about 900g a week selling twink items. The best part is there is no competition for the drops, just the AH and undercutting by a gold or two isnt all that bad. If you get more than one of the same item hold one till the other sells.
If youre not an enchanter then boss loot can just be vendored off...I d/e all BoPs and I put greens in the AH at a fair price. I made the money to buy my newest 60s epic mount in what amounts to about 3 hours of running lowbie instances solo.
Give it a shot.