My wife for Aiur
This game and to a lesser extent its expansion basically ate up most of my free time for at least a year after getting it back in 1998 and were one of the first games to introduce me to the rush of online multiplayer gaming and to the concept of sticking with a game as its community grew and the gameplay changed a bit with each released patch. While I had played several RTS games prior such as Dune 2, C&C: Red Alert and Warcraft 2, all great games at the time mind you, Starcraft easily trounced them all in most ways; here you got three very different but still well balanced factions each with their own detailed backstory, one lengthy and well presented campaign each (fully voice acted I believe) that tied into an overarching story of intergalactic conflict, and some nice improvements to the controls and interface such as building queues and rally points as well as a resolution boost.
On top of that there's the great multiplayer mode via Blizzard's then new battle.net service supporting FFA or team battles for up to 8 people, and if that's not enough for you there's the great map editor which allowed people to create their own spinoffs of the standard gameplay via user made scenarios as they were called, something that extended the game with stuff like RPG modes and zombie horde modes.
Of course, the base game with all of its nuances and depth was more than enough for me and with the continued developer support, the game soon became (and still is) one of the best balanced and plain fun RTS games out there.
