Getting on top of most buildings in Battlegrounds + Exploring

1. You need to level engineering to get the goblin glider tinker. Goblin Glider
2. You need to farm the rare elite in the vale of blossoms called "Kaltik the Blight". She/he spawns at the gate to the very far west of the vale of blossoms. This rare elite drops a trinket called "Bottled Tornado", which allows you to shoot up about 10-15 yards into the sky. 

How to:
During a battleground, find a building that you wish to get on top of, it cant be a building with extremely tall walls.

For an example i am using the wood mill atop Lumber mill in Arathi basin.

Stand on one of the hills behind lumber mill, use the bottled tornado. At the peak of the tornado use the goblin glider and you will rocket forward onto the building.

Another example is using a high ledge and propelling down to another building or area, the example i am using is from LM to the building on Blacksmith.

This technique can be used in other ways like exploring the battlegrounds. You can bottle and glide from a stand still below a cliff and get on top of it, assuming there is no barrier.

I use this technique on flag maps especially, you can grab the flag. On WSG i walk out onto the top of the alliance tunnel, pop the bottle and glider and it flies me over the center of the field to the entrance of the horde tunnel. On twin peaks i use this at the top of the alliance base and it takes me over 60% of the way to the horde base, well past the horde graveyard.