In my four years as a Napster subscriber (legal version, of course), I've defaulted to the program-based interface that became a bit clumsy and dated over time. Recently, I switched to the online version, which allows users to stream music without downloading external listening software. Now, after a significant redesign, the homepage looks way better and works much easier. [Homepage]
It haven't found anything better for long hours of computer listening. For $5 a month, you essentially get to stream unlimited songs from a cosmic jukebox and download five MP3s.