I'm thinking that DC power for everything from MP3 player to GPS unit, to laptop computer would work for me in my work, plus short adventure-exploring trips. A small solar array to clip onto my rear rack bag to have backup power for a laptop computer. A solar panel twice that size for clipping atop the same rear rack bag and a couple panniers, hung on either side of the rear rack, to drive a GPS for exploring obscure roads and trails.

I'm an older guy who's adapting my riding style and my bike from straight mountain bike, to utility, touring, recreational and commuting. I know other Baby-Boomers who are reaching retirement age, but won't retire, are doing similar stuff with their lifestyles and bikes. We're old enough that we're spoiled with having energy-consuming gadgets on board with us. And we have a variety of them, depending on the day's uses-needs.