Capcom's Nazo Waku Yakata (謎惑館) is a mysterious puzzle game that ditches buttons. Bye bye buttons!
Directed by Minoru Nakai, who previously worked on Resident Evil: Deadly Silence, the game features art by Tadahiro Uesugi and a scenario by Yukinori Kitajima, who wrote Sega adventure game 428 for the Wii and most recently Okamiden for the DS.
Players investigate goings-on in various rooms. The game does not use any of the buttons on the 3DS. It's a sound-based adventure game that uses the mic and the gyroscope as well as the touch screen.
Note: I haven't seen the game's official English spelling. Though, AndriaSang is reporting that 館 is being written as "Yakata".