Back in 1975, Brian Eno and Peter Schmidt created a creative thinking technique they called "oblique strategies". It was a deck of cards designed to spur creative thought at times when you are blocked because of pressure or external factors. You can buy Oblique Strategy decks at this site. From the introduction to the 2001 edition:
These cards evolved from separate observations of the principles underlying what we were doing. Sometimes they were recognised in retrospect (intellect catching up with intuition), sometimes they were identified as they were happening, sometimes they were formulated.
They can be used as a pack, or by drawing a single card from the shuffled pack when a dilemma occurs in a working situation. In this case the card is trusted even if its appropriateness is quite unclear...
You can also download a Dashboard widget that includes several generations of oblique strategies here. These are a great way to spur out-of-the-box creative thinking when you think you are stuck.