Google is offering new users a 90-day Trial of Google Play Music All Access for FREE (regularly $9.99/month) for a limited time. The service will continue after the three months at a rate of $9.99/month. be sure to cancel before hand if you do not wish to be charged.
Google Play Music All Access lets you listen to any music in their catalog of millions of songs, ad-free. If you have your own tunes locally, they will match them in the cloud and will store all your music in one place.