Digital Door Lock (2003)
The Idea derived from observing many people replacing their key operating door lock to digital (electric) door lock. However, they become useless when batteries are drained. This door lock fully funs by human-powered system where user windup the crank and it generates electricity to power the lock. It may be so annoying to crank everytime when user enter the house, but it suggests a way of slowing the pace of living through design - 'design for slow behaviour', and to use alternative power source, the human-power, that is much cleaner than battery.