Any Rules of Thumb for Planetary Spacing?

[Apollo7]

As I am often creating solar systems I'm wondering if you guys use any particular rules or systems for spacing planets, Bode's Law doesn't exactlymean much outside of our own solar system and what fun is creating something new if its exactly like what we've already got? I realize you probably shouldn't put planets so close together that they enter each others Hill Radius, but other than that what do you guys think when it comes to planet spacing and stability?