Ipod mini

driver less as in you can plug it in to any computer???
i know that ipods an nomads can be used as a HD (my friend had the 1st nomad like 4 years ago, very good, can do uncompressed recordings unlike ipod)

http://www.soton.ac.uk/~cah500/website/papers/atracmp3.pdf
thats a link if u wanna see the difference in quality

but now theres a surround mp3 format about to be released this june (prob be crap)
anyways atrac3pluss is the way to go, but AAC is good as its basicly 2 channel dolby digital (and dolby is discret unlike mp3)