Spotify's "Song Radio" mode is supposed to be its version of a Pandora-like radio, but it doesn't work that great and you can't see upcoming tracks. MagicPlaylists fixes both those problems.
When you type a song into MagicPlaylist, it will automatically generate a playlist for you. You can then save that to Spotify and delete tracks you don't want. The edit and save feature is actually pretty handy, especially since the playlists created are pretty good despite repeating the original artist a bit often.