When you disrupt your thought patterns, those ideas that create the greatest stimulus to our thinking do so because they force us to make new connections in order to comprehend the situation. Roger van Oech calls this a "Whack on the Side of the Head", and Edward de Bono coined a new word, PO, which stands for "Provocative Operation".
Try programming interruptions into your day. Change working hours, get to work a different way, listen to a different radio station, read some magazines or books you wouldn't normally read, try a different recipe, watch a TV program or film you wouldn't normally watch.
Provocative ideas are often stepping stones that get us thinking about other ideas.
Abutting ideas next to each other, such that their friction creates new thought-paths a technique that flourishes in the east (haiku poetry and Zen koans) but causes discomfort in Western thinking.