Check out three Christmas maps.
DEN 2005 Christmas Map: [Created by Lion] This is a 4-player team based or FFA multi-level Snow map, but works great in skirmish mode against the AI. Plenty of room to expand your base, and an adequate supply of cash to keep your army on the go. Each player starts with two supply docks. More money on the battlefield to fight over. The large mountain/plateau in the center of the map is filled with Christmas presents under the trees! A variety of tech structures including oil derricks and some tank crates scattered about the map. Lots of strategic possibilities with back entrances to the enemy camp. A few buildings and bunkers on the battlefield to garrison. Watch out for the train, which by the way can be garrisoned with troops and vehicles. The train will stop at two different locations for 20 seconds each time. You can load up vehicles and infantry and manually unload them at the next stop. I don't have it set for auto disembark.
-Christmas Map: [Created by DaRkAlEx] This is a moderately large 4-player symmetrical map. Takes place in a snowy environment (snow storm) with a town in the middle. Oil Derricks and a Supply Dock to fight over. A fun, balanced map for skirmish games against the AI or for all-out war online! Enjoy the map, Merry Christmas!
-Bozic: [Created by Pivac] This is a detailed 2-player Snow map with lighting set for night. Terrain is hilly and mountainous. Plenty of money along with goodie crates scattered about the landscape. Oil Derricks up for grabs. Good amount of room to build and expand.