There is no doubt that science and technology have improved the quality of modern life. Innovations like the personal computer, advances in HIV treatment and digital photography have become so accepted that it is difficult to imagine human existence without them. However, science is not infallible; sometimes things go wrong. In some cases, scientific failures just mean a trip back to the drawing board. In others, loss of human life is the tragic result. Below, in no particular order, are listed 10 major failures of 20th and 21st century science and technology.