Stern is on Sirius, a competitor to XM.

XM has a couple hundred channels, nearly all commercial free. Each station has a slightly different format & content. They are all grouped together, so if you are listening and want something a little harder you can just check up the dial one or so. XM has the broadcast from every single major league baseball game.

Because it's digital, you get info on the artist and song which displays on the unit.

A few years back I listened extensively, and found one station that was playing about 75% of stuff right out of my own collection.

There's one channel that, everytime it's 4:20 in any US time zone, they play a montage featuring a women yodeling and that wonderful sound of a bubbling bong.