Gotta love playful developers. Check out official Star Wars @ Spotify!
Spotify URI: spotify:user:official_star_wars
Spotify Link: (you need an account to see links)
They did the same thing with Nyan Cat a few years ago.
Uh, as far as I know there's only one way to do it:
1) Open Spotify
2) Right click a song or playlist
3) Select "Share"
4) Instead of "Share With Followers", select "Send To..."
5) Enter your friend's name and write them a message