Play Yan: Nintendo made MP3/MP4 player. Costs about $80 US and isn't currently in english.
It makes use of SD cards (same as GameCube and Revolution)
http://www.lik-sang.com/info.php?cat...s_id=6239&
http://gameboy.ign.com/articles/589/589659p1.html <- see samples
GBA Movie Player: Thirdparty hardware, costs $25US and plays movies/music/ebooks/pics/ and some games (a few of the NES games).
It use a non standard video/audio formatt (.gbm/gbs) so you are required are too convert everthing over.
(once you convert to .gbm/gbs you can't play that file on your computer, you can of course play the orginal file).
The GBA movie player uses the larger less standard CF cards.
http://www.lik-sang.com/info.php?cat...s_id=3983& <- clips at the bottom of the page.
The TV tuner let's you watch TV on your DS/SP
http://www.lik-sang.com/info.php?cat...s_id=6137&
The GBA AV adapter lets you plug in just about anything you could normally use on a TV (DVD, VCR, cable/satalite boxes, PS2/XBOX/NGC/PS1/NES/SNES/ etc etc etc) so long as it has the RCA plugs.
This retails for about $20 US
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