Gizmodo has a list of inventions that their inventor regretted making: http://gizmodo.com/5381696/regrettable-tech-inventions//gallery/1 Some of these aren't the worst things in the world, but some are pretty stupid inventions. Focus:What are inventions that you hate, or technology that you regretted buying? For me, there is no invention I hate more than the electric can opener. I don't see them too much anymore, but everyone used to have one when I was a kid. They fucking sucked, they couldn't hold the can, or get aligned with the blade, and half the time they stopped halfway through opening it. The old hand crank is dependable and can't be beat in my book.