I have a lot of playlists. Part of the reason is that I create new ones when I cannot seem to find one that I thought I had already created. As a result the list tends to grow.

It would be nice if I could search for a song (any part of the song title, artist, album, etc.) and get some listing or indication (popup, separate window, playlists highlighted, or whatever) that identifies playlists where I might find a match.

Being able to use a regular expression would be a bonus, but a simple substring would be a huge gain already.