MegaMek

The MegaMek suite of programs allow you to play out tactical turn-based battles and military campaigns in the BattleTech Universe, with tanks, infantry, battle armor, aerospace fighters, WarShips, and most importantly, the mighty BattleMech -- king of the battlefield. The programs provide a modern, computerized version of the BattleTech tabletop game, as well as a variety of features for running campaigns and customizing units.