Oddee has 12 cool low-tech inventions that are worth checking out, especially if you are interested in easy solutions to common problems. The laptop privacy thing pictured below is just silly, in my opinion.
But there are others look like truly great ideas, such as self-adjustable spectacles, a primitive refrigerator that uses only evaporation for cooling, and the rolling water container. The amphibious bike looks cool too, though unwieldy. Check it out.