IdeaChampions (www.ideachampions.com) are a great resource to stimulate your thinking and unlock fresh insights. I really like this attached article entitled 68 ways to be more creative at work: http://www.ideachampions.com/article_68_ways.shtml
It focuses on how you can easily add a quick creative catalyst or two to your daily routine. The suggestions I've tried out include: Starting an idea bank, spending more time with people in different fields and (weather permitting) going for a brainstorming walk with a colleague.
For an overview of how to facilitate a more formal Creative Problem Solving session the format I use is available at http://lifetravelling.com/2009/05/creative-brainstorming/
In the meantime, I'd love to hear what ideas you try out and how it enhances your creative capacity at work.