During the month of March, people who register a Nintendo 3DS or 2DS and one of six select Nintendo 3DS games on Club Nintendo will get a code to download either Pokémon X or Pokémon Y, the best-selling Nintendo 3DS games of 2013, for free. This insane promotion is only good throughout the month of March so if you haven't registered your system yet- hold off a few days!
To take advantage of this promotion you have to register your 3DS, 3DS XL or 2D between March 1st and March 31st, as well as one of the participating games. The six participating games are Mario Kart 7, Super Mario 3D Land, Animal Crossing: New Leaf, Donkey Kong Country Returns 3D, LEGO City Undercover: The Chase Begins and the upcoming Yoshi's New Island. If you buy them from the Nintendo eShop be sure to link your system before you do so, so you get credit. Once you do that you'll receive a download code for the game. Download codes for Pokémon X or Pokémon Y must be redeemed by May 31, 2014.
That's an absolutely fantastic deal on one of the most acclaimed games for the system, and unlike many promotions like this, the six you have to choose from to purchase are all great as well. There's not a stinker in the bunch. You could even pick up the upcoming, highly anticipated Yoshi's Island sequel and get it! It's like getting $40 for free, and consider the great deals you can generally find for 3DS bundles (the Zelda, or Mario & Luigi brands) you can get a whole collection on the cheap right now.
If you're a sucker like me who registered their system before this promotion, you get nothing! Sorry!
Otherwise, head on over to Club Nintendo and sign up.