Many moons ago I did Edward de Bono's Six Thinking Hats Short Course at the Melbourne de Bono institute. We also covered some of the material in the Lateral Thinking module of the Course in Creativity
6 Hats, as it's come to be called by most people, is a really useful thinking system. It's a simple constructive approach to getting groups of people to think together. Getting everyone to think about the issue in the same way at the same time really helps people cut to the chase.
I love using the hats to develop question sets to explore the issue or project at hand.
Wanna know more about the hats? Just Google 6 Thinking Hats.