We've already seen plenty of creative StarCraft II mods change the real-time strategy game into racers, side-scrolling shooters and more. But modder Mads Lund's injection of futuristic, zombie apocalyptic, third-person shooting may be the most promising.
This is Lund's "Ruins", a StarCraft II modification using the game's Galaxy Map Editor tools to create something very different from the standard gameplay of Blizzard's real-time strategy game. Give it a minute to kick in, so you can see how encouraging this mod is looking. Sure, it may not replace a Gears of War horde multiplayer mode for your waves-of-killing needs, but it's a neat tinkering with of StarCraft II's guts.
AC130K - Ruins (Starcraft 2 zombie shooter map) [YouTube - thanks Mads!]