Personally, I'm a big fan of Edward DeBono. Two of my favorite books are: 1) Lateral Thinking: http://tinyurl.com/88ugdjz 2) Six Thinking Hats: http://tinyurl.com/7t2w27y . There is a video course available on youtube as well: http://tinyurl.com/6q4rz2t I learned about them through Alan Kaye's reading list: http://tinyurl.com/83bqlbx He has a section on learning and creativity that has some other good alternatives.
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