Gizmodo reports on the sighting of a Nintendo DS MP3 player option that will be in available in Europe soon.
MP3 audio files are stored on a SD card (up to 2GB). Using Apple’s estimate of 1,000 songs on their 4GB iPod nano, the Nintendo DS option could store up to 500 songs when using a 2GB SD card.
There also an earlier reference to a Nintendo DS Opera Web Browser cartridge.
This links to a YouTube video review of the Opera Browser cartridge available in Japan.