With the release of 1.9 came the infamous introduction of the AQ instance/loreline. Along with this new challenge came an amazing list of new loot.
Of course, every hardcore raider wants this. Unfortunately... this requires an intense faction grind. Enter money opportunity.
There are 3 twilight camps located in Silithus. One just west of Cenarion Hold, one northwest of cenarion hold, and one far southwest, near the gates of Ahn'Quiraji.
The twilight camps are populated by Twilight Cultists, enemies of the Cenarion Circle. These mobs range from 58-60 in level. Each one killed awards you one rep point. In addition, they have a % chance to drop four other useful rep-related items: Twilight Cultist Cowl, Twilight Cultist Mantle, Twilight Cultist Robe, and Encrypted Twilight Text. The texts are turned in for rep or mailed reward (depending on which of the 2 npc's you hand it over to). The cultist pieces are used to summon templars from wind stones.
Step one:
Goto a twilight camp, start killing mobs. Be careful, they love to come at you in packs, and because of their high level they can do some decent damage. As a 60 rogue geared in all blues and bloodfang pants, i can kill one in about 10-15 seconds. They drop major healing pots and runecloth in addition to the 4 rep drops. Once you get a full cultist set, you're ready to summon a templar. I'm combat spec and can solo them w/o too much trouble if i pop a healing pot and use my cooldowns. They're 60 elites so they do hit kind of hard. They drop green BoE's that will auction for 5-10g. Each templar also has a 3% chance to drop a blue BoP. They each have a certain one they drop. Keep it for upgrade or DE.. it's nice stuff.
Now for the real money. When you get a stack of 20 twilight texts (20-30 mins for me) you can visit auction house. I usually get about 40 and then take a break, because i don't have the attention span for hardcore farming. On Icecrown, i can auction a stack of 20 for 20-25g. So in the past couple days, i've sold 4 stacks. 100 gold for about 1.5-2 hours of invested time. This is one of the most stable money making strategies i have been able to come up with. It may be a limited window type thing, as sales will dwindle as more people hit revered/exalted goals for their gear.