At least one woolen blanket
Food (military MREs, at the moment)
Tea AND packets of sugar
A pocketknife with a can opener blade
Toilet paper
A large plastic trash bag
Telescoping snow shovel
Can or something to melt snow in
A paperback book or two
Sterno (jelled alcohol fuel) and a small stove for it
Plastic mug and bowl, w/plastic fork and spoon
Pencils and a notebook
A gasoline tank that is always at least half-full
The knowledge of how to use the above