White Smoke Flare

The White Smoke Flare item is a pyrotechnic device used primarily to mark a location by placing a white smoke column object on the terrain.

Some uses that people have come up with:
 * marking locations for raids
 * smoke bomb the Flag Rooms in the Warsong Gulch battleground
 * props for floor shows and fashion shows
 * effect for Role-plays involving burning buildings/areas/etc

Source
White Smoke Flares are crafted by Engineers with a skill level of 335.

The is sold for  in limited quantity (1) by: The White Smoke Flare schematic does not bind, and can be bought and sold at the Auction House.
 * in Zabra'jin
 * in The Exodar
 * in Shattrath City
 * in Silvermoon City

White Smoke Flares are sold for in limited quantity (3) by:

This item is also available for free (!) in limited quantities by
 * Bossi Pentapiston at Toshley's Station in Blade's Edge Mountains
 * Gordie in Shattrath City (near the southeast exit)
 * Irradiated Worker and Qiff at Area 52 in Netherstorm

The White Smoke Flare item does not bind, and can be bought and sold at the Auction House.