That game for me is The World Ends With You. It was my first time playing it this year (its initial release was in 2007). I played the original DS version and I love how beautifully weird the game is. From the controls, to the story and characters, and to the music, just a really enjoyable game. Reminds me of why I like Japanese games. They can be very artistic.
So what about you, SW? Last game you played that was at least 10 years old?