My favorite is called "How to think like Leonardo da Vinci" http://www.amazon.com/How-Think-Like-Leonardo-Vinci/dp/0440508274 http://www.amazon.com/How-Think-Li

My favorite is called "How to think like Leonardo da Vinci" http://www.amazon.com/How-Think-Like-Leonardo-Vinci/dp/0440508274 http://www.amazon.com/How-Think-Like-Leonardo-Vinci/dp/04405... It also has a companion workbook. Who wouldn't want to think like Leonardo !