So I'm sure quite a bit of people know about the fire extinguisher that gets placed on your back when you're doing the quest in Northshire. However, that one does not work outside of Northshire, this one however, does.
So, let me start off by saying this is Alliance only. Alright, we'll be heading on over to Gol'bolar Quarry, located in Dun Morogh, here:
We're going to do a couple of quests there, and then we'll get a breadcrumb quest go visit another questing location, lcoated near Helm's Bed Lake:
Alright, we'll do 2 quests here, turn them in, do one more quest, and then we get a quest to go to the Ironforge Airfield. If you have a flying mount, just fly there, else go west a bit and take the chopper up there. When we arrive, turn in the quest, and pick up the new quest "Extinguish the Fires". Congratulations, you're done! The whole process took me about 20 minutes.
SOME THINGS TO NOTE:
1) It stays upon switching continents
2) It stays upon switching instance zones, such as going into a dungeon / BG
3) It is lost upon death, HOWEVER once you switch continents it will be back. I need to do a little more testing on how to get it back, but I died in Darnassus, ported to SW, and it was back.
Here's some random screenshots of it:
In a BG:
In Darnassus:
This is from a POV of a different account of mine, showing that other players can see it: