Instead of a chemical-process single-use hand warmer which leaves you a packet of goo that you have to throw out, pick up a Sanyo hand warmer plus a Sanyo Eneloop.  The Eneloop is a solar-powered AA battery charger, which is paired with the hand warmer if you like, or you can just sneak the batteries into your Nintendo DS.  Unlike old-school rechargables, it also comes ready to use, no initial charge necessary.   [GT]

Sanyo Eneloop [via Cocolico]

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