www.justintv.com has licences so you can stream certain kind of music, videogames and even movies. The only licence they dont have is for FOX and Disney Music/Movies.
So it depends on which plattform you stream, s just not easy to find the right ones (and they are full of commercials/adds cause they have to pay for their licences). Plus justin.tv is not full free, there are advanced accounts you have to pay for.