Real Networks talks about its online music subscription business, on the Internet Stock Blog:

In 2004, our music revenue grew by more than 350 percent over 2003 and we became the clear leader in music subscriptions with over 700,000 paying subscribers… we operate what we believe is the largest network of subscription music listeners. Our RHAPSODY subscribers played over 239 million on-demand songs during the fourth quarter

iPod and iTunes get most of the ink, but prospects look bright for the subscription model as well.