my harddrive is only 70 gigs, however it spins at 10k rpm and is SATA, its one of those western digital raptors. it works great for me but its not big! if i had kept all of my music which is now 18 gigs and at 128 then it would be 36 gigs if it was 256! if it was 320 it would be 45 gigs! see how much it adds up! you were saying 'oh its just 7 mb' but i mean if you apply that same concept to over 10,000 files then you have a serious problem if you are low on harddrive space, lol plus my mp3 player is only 256 mb, lol. however windows xp only recognizes it to be around 245mb : (. i can therefore fit 261 minutes of music on it if it is in 128 cbr mp3 format, roughly the same as 3.2 full stocked audio cds, not bad by my standards. ( 64 seconds of music on 128 cbr mp3 format is exactly 1 mb) and i can change it instantly. but if i load it with high bittrate mp3s then i can only fit about half of that on there : ( and its not like a 256 kbps mp3 will sound TWICE AS GOOD compared to a 128, because it doesnt. it sounds a little better but has twice the size. bottom line, 128 kbps is the perfect balance of quality and filesize.