UAV recon
Once this things up, the whole game changes. The pace of the game steps up, campers are like f**k, the kill feed goes mad.... its just so awesome and so under-rated. I dont understand why anyone wouldnt pick this.
I always pick this and counter-uav so I can have it and the other team cant =P
Edit: Actually im not even sure if its classified as a powerup.... but who cares.