This is the perfect hefty loot item -- it's easy enough for almost anyone to get, but relatively secret enough that most people don't know exactly where it is. When I came across it leveling up my Hunter this week, I knew it belonged right here.

Name: Orb of the Blackwhelp (Wowwiki, Thottbot, Wowhead)
Type: Common Consumable
Damage/Speed: N/A
Abilities:

• Transforms you into a helpless Blackwhelp dragon for up to 15 minutes. You can't attack or cast spells while transformed.
• In fact, it's pretty limiting -- you can't even take damage while in this form. You can use self-buff abilities and drink potions and such (rumor is that Winterfall Firewater looks funny while the Orb is on), but the disguise is pretty fragile.
• And Wyrmcultists will see right through you in this disguise, as will any other mobs. We'll get to why that's important in a second.
• Oh, and coincidentally, Blizzard's item ID number for this item is 31337. Cute.

How to Get It: Up in Blade's Edge, in the Wyrmcultist chain of quests leading out of Evergrove, you'll eventually find your way to Blackwing Coven, a cave west of the Grishna Arrakoa settlement (through the Wyrmskull Tunnel). There's a quest called "Meeting at Blackwing Coven," that requires you to kill Wyrmcultists, get "Costume Scraps" from them, and then use five of those to make a costume that will make you look like one of them.

The actual quest has you meeting with an NPC and then leaving, but if you hurry (the costume only lasts three minutes), you can run over and also chat with another NPC on the opposite side of the cavern from the quest target. The NPC is called the "Wyrmcult Provisioner," and if you're in costume, he'll be friendly, and act as an actual vendor. Among a few other general goods (I stocked up on bullets while there), he also sells this item for a mere 2g 50s.

And the good news is that even if you've done the quest already, you can go back, murder more Wyrmcultists for more Costume Scraps, and go visit the provisioner again. So even if you didn't catch this the first time around, it's still waiting for you in Blade's Edge.

The Provisioner also sells the Wyrmcultist's Cloak, which is a nice Fire Resistance cloak, especially since it's so easy to get.

Getting Rid of It: It's only got 3 charges, so use those and it's out of your life forever. You could also sell it back for 62s 50c, but unfortunately it's BoP so no auction house profits off of this one.