[garyrob]

I get that effect while walking, but also from multi-hour highway (not local) driving when the road isn't crowded. Somehow, having my body do something that takes only a slight amount of continuous awareness, but not zero, seems to enable me to escape mental ruts more easily. For me, it allows for deeper concentration in the creative realm than I can have while sitting.

Friedrich Nietzsche: "Only thoughts reached by walking have value."

[velcrovan]

David Gelernter describes a theory of consciousness and creativity that explains why this works in his book “The Muse in the Machine”. I recommend it to everyone.