<a href="http://pocketspc.pocketheaven.com/" target="_blank" >Gary Linscott</a> has updated his Snes sound player for the Nintendo DS:
Tons of fixes in this version, most songs sound quite a bit better.
Check out the readme.txt in the archive for how to set things up. Note that you need the .NET framework 1.1 installed to run the rom builder.
Keys for the menu system:
Up/Down - move the current selection. The name on the top is the SPC that will be played.
A - start the current selection playing
B - stop the SPC and go back to the menu system