small flashlight uses one AA battery, good for months. no camping, but
power often goes off in asian countries. digital camera uses a couple
AA's, good for around 400 or so pictures. i carry 4 spare batteries....one
set in the h-bar bag, one set in the panniers. recharge as needed, usually
overnight once every couple weeks. recharger weighs about an ounce.

cell phone (if not left in sock drawer) battery will last up to a week. turned
off wifi and blootoof and gps. mostly text messages or rare short call.
recharges in 2-3 hours. this recharger also weighs an ounce.

paper maps. no batteries required.