For me, I've been into the half-whole stuff and melodic minor for a long time... Until recently when I found out that I can use the harmonic minor scale in jazz. The modes of harmonic minor are so much more versatile than melodic minor, too. I mean, you've got major 7, minor 7, dominant 7, even diminished 7! I've been getting some really original sounds out of it, too. Mess around with it, you'll like it. Harmonic minor is cool. That and altered pentatonic scales.