bpoint ported their original PC-based musicdisk “Brainstorm Annual 2010” to the NDS. The musicdisk features 26 songs in a mixture of streaming (.ogg) and various module (.mod/.xm) formats, with nifty visualizers running at a full 60fps. Sound quality is extremely good when using headphones or earphones (the internal speakers are OK, but not great).

Discussion: http://forum.gbadev.org/viewtopic.php?t=17382