So this is something I discovered by accident but ever since, I have made tons of gold. It is also another incentive to do pugs while you are downtime. I will give you an example of when I would make 4-5k a day doing this scam before the expansion, but I still do it now but not as much money!!!!
Ok so I would pick up an UBRS group with my level 60 rogue. In UBRS, the newest rank of Eviscerate would drop off the assassins. I would usually try to be the only rogue in the group but would also be ok with 1 other one. Everytime I ran the instance, the book would drop about 60% of the time. When it did, it is CLEARLY a rogue only item, so if you needed it as a rogue, you would have an option to roll need on it...So you would have priority. Of course if you already had it, then everyone would roll greed and whoever won would make 6-700 gold on it in the AH...Well everytime I would pick up a pug, I would ALWAYs tell the people "YES OMG I HAVE BEEN WAITING FOR THIS TO DROP FOR WEEKS NOW!" When they saw the joyment they wouldn't hesitate to congrats me on the drop. I would then just trade it to a lvl 1 alt and sell it in the AH.. On a good day I would make thousands of gold doing it.
SOOO before you go on and flame me, I just want to say I KNOW that no one does UBRS anymore...So I changed the way I do this scam. I still pick up pugs, but now, when I item drops that is usefull for your class but you already have something better or whatever, take the item off (make sure in your settings you deselect Show Cloak and Show Helm so they can't see what you are wearing on your char) and put a crappy one on that you carry with you. At that point they will check to see if it truely is better. They will see that it is better because you have the crappy one on. So roll need and win the item. You can then DE it and sellin AH...it's cool cause the shards from outlands are worth booko bucks.
So next time you are bored and pick up a pug, have this in mind

you will be surprised and a lot of times end up banking 100-200 G with this technique. It's even better when you find a BOE that you can sell in the AH..just make sure you have 1 of each body slot items in your bad, for example, make sure you have a pair of boots, gloves, chest, necklace, rings, ect ect in the your bag that you could potentially switch when an item drops. As you can imagine, it might be a little difficult to convince them if a weapon drops since your weapon is displayed on your character model, but when you get good then it gets easier.