These solar-powered LED lights by Miniwiz illustrate the true potential of design intersecting ingenuity. Re-purposing the ubiquitous plastic bottle — that heinous bane of the enviroment — into a usable light source, Miniwiz have transformed a liability into an asset. You just screw the LED lights in place of the cap and leave it outside. Via the solar cells, daylight is converted to power the bulb at the top of the bottle, automatically activated by a built-in light sensor. Weather resistant and sturdy, these are available at HYmini for either $25 each or 5 for $100.