LightCap by Simply Brilliant (names say it all)
I like to spend whatever free time I can muster in the outdoors, but generally go fairly lightweight, so might never carry the LightCap myself. But that doesn’t mean it isn’t a very bright idea. Imagine a 1litre (32 oz) polycarbonate wide-mouth drink bottle, then fit a solar cell into the exterior of the cap and a energy efficient LED light in the underside. Charge up the solar cell during the day, and at night you have a virtual fluorescent light for camp. If the photos are accurate, it looks like the light refracts through the water, making the light broader spreading that it would be on its own. If you can manage 12 hours of direct sunlight the LightCap will provide 8-10 hours of illumination (or more than 16 hours if you switch it to the energy, and night sight saving, red LED mode. The rechargeable (and replaceable) Ni-Cad batteries are said to last through 300 cycles. The weigh difference over a similar, yet ordinary unlit,, drink bottle is 4.6 oz (130g). This is about the same as small LED headlamp, so there is no overall weight saving for gram counters. But there is no disputing the cool factor of these waterbottles. Set a LightCap going after dark and your tent-site will probably attract other campers, like moths to a flame. ::LightCap
LightCap with red LED a glow'n.