Nintendo is offering a cool eShop promotion to encourage purchases of two newly released titles in the 3DS eShop, Art Academy: Lessons for Everyone! and Crossword Plus. Purchase either of those through the platform's online store and register it by January 6, 2013 and you'll receive Donkey Kong: Original Edition as a free download.
You'll need to sign up for Club Nintendo and then purchase either game through the 3DS eShop to take advantage, of course. Art Academy and Crossword Plus each sell for $29.99. The free Donkey Kong won't be available for purchase and it includes content that hasn't been seen in the U.S. before. Presumably it's the same updated version of Donkey Kong (featuring an extra stage) that was given away in Japan with New Super Mario Bros. 2 eShop purchases.