HLA stands for High Level Architecture, and is an IEEE standard for simulation modeling in the DoD world. It basically makes sure that all these simulations located in, oh, I don't know, NORAD, space, what have you, can talk to one another and pass information without crashing or otherwise screwing things up. Is it a boon to military simulation modeling, or the next ADA? Only time will tell, but this is for sure; to date there is no corollary activity in the civilian world to simulations as extensive and comprehensive as what the military does. Unless you count StarCraft.