Have you been waiting for Warcraft 4? And waiting and waiting? Then you'll be glad to know that intrepid modder StevenLuo has brought Warcraft aesthetics to StarCraft 2 using the SC2 Editor. The finished product, WOW RTS: Alliance and Horde (or WAH for short), features 2 factions, 16 units, 18 heroes, and 3 maps -- Lost Temple (2V2), Crossroads (1V1), and Ashenvale (1V1) -- which you can play on with others or against the AI.
Can't wait to get started? Launch the StarCraft 2 Arcade and search for WAH to bring up the maps. The initial download is 245MB, but once you have all the assets, the individual maps are pretty small. So what are you waiting for? Get Warcrafting!