now this is truly old school:

TACOMA, Wash. (AP) — A snowshoer who was lost in a blizzard for two days on Washington state's Mount Rainier said he stayed alive by digging out a snow tunnel and burning the dollar bills for warmth.

Yong Chun Kim, 66, of Tacoma, said he carried a lighter and other emergency supplies and burned personal items: extra socks, Band-Aid, toothbrush, packaging, and lastly $1 and $5 bills from his wallet.