Zelda SFX is a collection of all sound effects (and currently) one background music track) found ingame. You can play the SFX and play with volume, speed and pitch, which could lead into short amusement.

Thanks to http://www.nintendomax.com/viewtopic.php?t=13829&f=19 and http://gbatemp.net/t308021-zelda-sfx-ds for the news.

http://gbatemp.net/t308017-zelda-sfx-ds