Nintendo is "celebrating all things Hyrulian" for a limited time by giving away the Legend of Zelda: Four Swords anniversary edition for free for the next four days on the 3DS/2DS. Nintendo offers instructions on how to download the game right here:
The game is available starting now until Sunday, February 2, at 11:59 p.m. (PST). But if you miss out on the deal, there's more Zelda coming soon: The Legend of Zelda: A Link to the Past is coming to the Wii U eShop (it has been available on the regular Wii shop for a while), and there will be "a special Art Academy SketchPad event in Miiverse." Unfortunately, there's no announcement about bringing A Link to the Past to the DS eShop.
In related news, you might have seen that GameSpot gave our 2013 game of the year award to The Legend of Zelda: A Link Between Worlds. If you haven't played it, I've heard that the game is pretty good.