Leonardo Da Vinci *

http://www.scuolaleonardo.com/

_ Perpetual Motion - Leonardo da Vinci's Machines Part 1
http://youtu.be/xDF0cugCoMM
_ Leonardo Da Vinci Full Documentary
http://youtu.be/wnV4bkPkZQM

http://www.dilbert.com/strips/comic/2014-04-14/