in reply to Eureka!

Like for the others here it mostly happens to me when my attention is detachet from the problem. Usually it happens at lunch.

There is a guy analysing more 'active' ways to 'creative thinking': Edward De Bono. I have read just one book by him - but it was really thought provoking, and I am determined to read some more. What he proposes are some techniques for random playing with problems.