my new favorite toy is the diminished scale.It's wierd and I have to think of in in intervals to keep it in my aged mind.From wherever you start go whole step then half step and keep going the same way.In a recent jam a guitarist started playing diminished chords but used a basic blues framework for the chord progression.It's the only time I have had a chance to use it other than just sitting sround noodling but it's fun.the japanese 5 tone scale is similar.It is root,flat 2nd,3rd,4th,and fifth.A little easier to work with though