The radicals behind the French Revolution wanted to remake the world in vision of their new, rational, modern ideology. One of the greatest legacies of this tendency was the metric system, which replaced the old confusing inches and pounds and feet with logical factors of ten. Lesser known is the attempt to duplicate the feat with time: the French Revolutionary Calendar, with its ten-day weeks and ten-hour days. This seemed eminently reasonable, but conflicted too much with custom and the rhythms of people's lives, and was eventually dropped by Napoleon.
Many tech visionaries similarly sought to completely remake the world. Sometimes it works, but, as in the case of these 10 failures, often it doesn't.
This slideshow originally appeared on ITworld.com.