Not something I'll be bothering with, but I'm just wondering whether anyone had tried a battery-powered heated jacket for keeping the cold out?
E.g.
http://www.bunnings.com.au/aeg-12v-h...cket-_p6230202
I imagine it raises a whole new class of "First-World Problems":
"I can't go star-gazing tonight because i forgot to recharge my jacket!"