Tinysong.com
Interesting site I came across today. Tinysong.com is kind of like a TinyURL for streaming music. It looks like it pulls from the apparently new Grooveshark, which I'm not too familiar with. Type in a song title, artist, album, etc, and it lists songs available. Choose one from the list and it copies a short URL to your clipboard to use as you choose. Well done, and from the digging I did, it has a fair amount of ambient music from some of the more popular artists.