It is a little shame that Pandora.com does not work anymore in Europe. But you never know what is around the corner. I found out that last fm has got the same funtionality and more.
A great plug in for Firefox (look for fire.fm at add ons) let you enjoy almost any kind of artist. The same functionality is being used in order to let them decide which artist are similar to the one you choose.
While opening Firefox you just listen to you favorite artists (or alike) without going to last fm site.