Creates playlists based on mood and learned likes and dislikes. Cartesian graph with Energetic —> Calm on the y-axis, Dark —> Positive on the x-axis. Can narrow results by music genre and decade/time period.
Must also have a system (via the likes/dislikes maybe?) or determining a group consensus on where each song falls on the graph. Is on a song-by-song basis, not by artist, though I wonder if it takes that into account (e.g. My Chemical Romance weighted towards Dark and Energetic, etc.)