Since having read How We Decide, I've been checking out Jonah's blog over at Wired. Last week he posted "How Do We Identify Good Ideas?"
I think his post is highly applicable to chess. Josh Waitzkin also discussed a similar idea in his book Art of Learning.
In a nutshell ... if you need new ideas (creativity), do some brainstorming and then distract yourself for a bit before returning to the problem at hand. In chess-speak, when confronted with a critical problem or position, identify your candidate moves. Once you think you have the one you need, walk away and distract yourself - preferably by doing something that makes you happy. Then come back to the problem and reassess.
The distraction part allows your subconscious to take over and make connections. And when you let your subconscious work on the problem a bit, your chances of getting a better result go up.