Because one launch isn't difficult enough, Arma devs Bohemia Interactive are going for one-and-a-half today. The big one is Argo [official site], their free multiplayer FPS spun off from Arma 3 [official site]. The half is an update for Arma 3 adding a new island to play on, the remake of Operation Flashpoint's Malden which Bohemia made for Argo. All this is to celebrate the 16th birthday of Flashpoint (or Arma: Cold War Assault, as Bohemia later renamed it) today.
[Update: Because I'm a big sleepy fool, this post originally included the release of an Arma 3 expansion that had been out for a month.]
So, Argo is a free FPS which takes Arma's serious shooting to game-y modes based around capturing points. Argo also introduces a new 12-player cooperative mode, Combat Patrol, which procedurally generates missions across Malden.
Bohemia released Argo in prototype form a while back but now it's properly launched, available on Steam. Good luck getting to the store while it's overloaded due to the start of the Steam summer sale. Argo is free, though Bohemia are selling a £7 'supporter pack' of cosmetic bits like victory animations.
Today's Arma 3 update rolls in a little of Argo. It adds the Malden 2035 island and Combat Patrol mode, while also also improving the flight model of Arma's jets and making other changes. Check the patch notes for the full scoop on everything.
Oh, and of course everything Arma is on sale on Steam.
Malden 2035 is a pretty place: