Solar charger for phones tablets and your etceteras....
I bought one of these a year or so ago and its still going strong;
http://www.ebay.com.au/itm/For-Samsung- ... rQL3TjEeJAI bought it as we were going overseas and I just did not want to run out of power for my camera or computer....
It does charge my ASUS T100, Nikon Camera Battery and mobile phone; not all at once though in fact it only will charge the ASUS once without recharging...
Could come in handy free camping....
Hardly used it in Vietnam and China most places had mains power.... But it did come in handy for the camera batteries, I was taking something like 500 a day....