This is so simple. Continuance is a set of batteries with a USB interface on the side. The batteries are rechargeable plus dole out some juice to stranded gadgets that are starved of power. Handy, compact and a totally do-able concept! Kudos! Continuance is an iF concept design entry for 2011
You can actually buy solar powered yachts as well as speedboats now. Cool idea.
here you go.