I'm a musician, too. I meant that someone could start a GNU FM service and stream music that has been licensed legally from musicians.
http://magnatune.com/info/give
So letting the whole world listen would break the agreement, but just streaming to you, your spouse, and maybe a buddy or two would be "OK" or at least well within the spirit of the agreement. Just no more than 3 other people. I'm not exactly sure why you'd stream rather than just share the file, but whatever. Maybe you have purchased gigs and gigs of music licenses and want a jukebox effect, donno.
I've purchased rights from magnatune in the distant past, and would recommend them. I like their business model and they did the deal professionally and quickly, and I've not heard anyone complain about them. Good people, basically.