The next time you're stumped on a creative challenge, head to a bustling coffee shop, not the library.
Instead of burying oneself in a quiet room trying to figure out a solution, walking out of one's comfort zone and getting into a relatively noisy environment may trigger the brain to think abstractly, and thus generate creative ideas.
This works for me. Once or twice a week I head out to a local Starbuck's towards the end of the day and quote deliberately think about the things I am doing and am planning. It's where I get some of my best ideas.