From GameBrew - a wiki dedicated to Video Game Homebrew.
'ramming Santa is a Christmas theme homebrew game with WiFi supports for the NDS. Up to four players can play over WiFi, and a single player game with 3 AI's is included for practice.
It is created for the Drunken Coders Third Annual Christmas Game Coding Competition.
How to play:
Your goal in this game is to program your player to pick up the gift and deliver it to any of the sleighs.
You'll be competing against up to three other players, so watch that they don't push you into the water to slam into you to steal the gift you might be carrying.
In order to host a game, you will need to hve your router forward port 9999 to your DS. IP address of can be found on the WiFi menu screen in game.
If you don't have port 9999 being forwarded to your DS, you can still host a LAN game, just be sure that the other DS's that try to join use the Join LAN Game option rather than the Join Game option in the menus.
Operate with Stylus.
R4iSDHC (firmware 2.7e)
Ultra R4 (firmware v1.56)