Using smart playlists to organize music by properties helps me find music I want to listen to in my iTunes library. Simple titles work well when the playlists are in a single folder ("Indexes" works). My iPod carries "Underrated" transit time is rating time. I have made steady progress towards rating every song. Complex indexes can be built out of simple components. Playlists such as "Top Rated" and "Checked" encapsulate a set of logic selections as a single "smart playlist". The logic "playlist" is then used in other "smart playlists". Some simple-seeming playlists can only be defined with complex indexes. Many of these playlists depend on song ratings. Consciously-selected metadata helps improve the "success rate" of the playlists. To rate songs, I use Synergy to bind F1 through F5 to the rating stars in iTunes. Others might bind F6/F7 to increase/decrease by a half-star. Most of the playlists are at their best in Smart Shuffle with no more than 5 upcoming songs listed. This reduces the delay between when a rating is changed and when the new rating takes effect in Smart shuffle. All rating-logic playlists refresh immediately when a rating is changed. These playlists simplify using and maintaining an iTunes library. Finding something to listen to takes less energy with these indexes. Genre alone has limited usefulness. I have many more of these. Feedback is welcome. I don't use half stars. "5 underplayed" lists 5 star songs that haven't been heard recently, providing an instant "mix" of great music. Match the following rule: My Rating is |*****|. Limit to 100 songs selected by least recently played. Live updating. "Checked" lists all songs that are active in the library. Limit to 10000 GB songs by name. Live updating. "Top Rated" lists active songs that have at least 4 stars. Match any of the following rules: My rating is in the range |****.to|*****|. Live updating. "Unchecked" lists all songs that are not active, using the "Checked" playlist. Match the following rule: Playlist is not "Checked" Live updating. "Underrated" lists all songs played with no rating stars set. Match the following rule: My Rating is |.....|. Live updating. "Unplayed" lists good songs that haven't been played recently, using the "Top Rated" playlist. Match the following rule: Playlist is "Top Rated". Limit to 100 songs selected by least recently played. Live updating....