I'm very particular about what I strap to the outside of my backpack. I don't want anything heavy swinging around to distract my cadence, especially when I'm peeling off significant miles. Gear strapped needs to be lightweight and of the utmost necessity (e.g. tarp, hat, suntan lotion).

Bethany over at DIY Life recently highlighted a new, intriguing product that fits my ultralight hiking standards and makes for a greener footprint, too. The new LightCap 200 by SolLight is a 2.6 oz cap that screws onto any standard wide mouth water bottle to create a solar-powered lantern. No more lantern batteries to carry, no dripping candles to burn. Four SuperBright LEDs offer six hours of light on a full charge. Unscrew the cap from the bottle and you've scored a mini-flashlight, too. The cap costs $19.95 -- photo from www.sollight.com.

The arrival of this new product couldn't be more timely. By now you've likely read about heightened concern surrounding water bottles (e.g., Nalgenes) and other products containing the controversial chemical BPA (bisphenol A). BPA is linked to a host of ailments in animal studies. Major retailers are shunning some BPA-tainted products, and Nalgene amazingly announced last week they will no longer be manufacturing water bottles with BPA. Turning your old BPA water bottle into a solar-powered lantern is a good solution. I know I'd be willing to snap this solar cap on my pack.

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