diminished whole tone is a favorite of mine when I want to insert a nice colorfull run.....sounds cool when played over a minor 7th chord, starting a whole step above the root.
ex: Dmin7
Edim/wh (C#) D E F G Ab Bb C D
C# leading tone makes for a colorfull entrance

Been playing a lot of Nylon string lately, I enjoy playing with Harmonic Major
E F# G# A B C D# E
I find the F# can be interchangable with F natural for some nice colorization.