Even inventors have bad days. Take Thomas Edison for example, who revolutionized our world with the light bulb and the phonograph. He also created a concrete piano and a machine to speak to the dead. Edison was not the only one to engineer a complete flop now and again; in fact, failure amid greatness is the norm – not the exception. From Alexander Graham Bell’s multi-nippled sheep to Leonardo da Vinci’s walk-on-water shoes, these ludicrous ideas will leave you with a smile on your face, and a new perspective on the meaning of success.