Eight Common Things Invented or Discovered by Accident

1) Penicillin - 1928, Alexander Fleming
2) Play-Doh - 1955, J&N McVicker
3) Potato Chips: 1853, George Crum
4) Corn-Flakes: 1894, JH Kellog
5) Post-it Notes:  1974, Arthur Fry
6) Microwave Ovens: 1945, Percy Spencer
7) The Slinky: 1943, Richard James