Using video game technology and animation, the U.S. Army and Homeland Security Department have developed a computer-based simulator that can train everyone from teachers to first responders on how to react to an active shooter scenario. (Dec. 27)
BBC had a more indepth look into the gameplay, which features the ability to move objects in front of doors (which is very fitting in light of @FuckYou's atrocity). For hopefully obvious reasons this game will probably never be public, but there is a free version for teachers coming soon. Academic kiwis please leak.