What would be your desert island 84rack selection to give you plenty of time to explore with...?

Something that can run off of a power brick with a solar charger in the mix. That's about 1000mA or so of usable power.

An AE system. Honestly, when it comes to energy efficiency, the AE Modular system kicks the crap out of everything else. There already are producers using theirs on solar, battery power, etc. It's also smaller, lighter, and...quite significantly...CHEAPER.