I'm tinkering with The Tüül (https://github.com/incidentist/the_tuul), a site for making a decent karaoke video from any song in about 10 minutes. The members of my monthly karaoke group have been using it for the last year and it's been great to see what they've made. There's a lot of potential for automating some of the markup (such as count-ins, and INTRO/OUTRO/INSTRUMENTAL segments) but I need to redo the data model to make it easier to work with first.