I've got a steel billy can like this...
Actually, it's this
...stuffed with matches, small bic lighter, waxed cotton balls(firestarters), Fox 40 whistle, 2x foil emerg blankets (they're packed so small when new), another (more permanent) orange emerg tarp, beef stock, instant coffee, sugar, non-dairy creamer, ibuprofen, a 5" folding knife, Leatherman, some 20-odd feet of mechanic's wire, and a MEC Turtle LED. I chuck this in my pack every time I ski and 'might' ski under the rope and out of bounds or go for a scramble. I've read too many news reports of people spending the night out and miserable after getting lost. If that were to happen to me, I want to be able to offer the guy that comes to get me the next morning a cup of hot joe.
I will also make sure my phone has a good charge on it (Whistler Blackcomb and environs has good cell coverage).
I keep a freezer ziplock on standby with a change of (non-cotton) base layer top & bottom, a fleece and dry socks.
Surprisingly, all this will go into a full-sized camelback with still room for a bladder, sandwiches, a camera and GPS/map for day trips.
I also need to focus more on first aid supplies.
All this on top of whatever I might consciously pack for a longer outing, such as food, headlamp, shelter, water/filter, extra layers etc.
For something like the Chief I would omit a ton of this gear, as help is close to hand if necessary, but for anything more remote or possibly off-trail, I've got it (I base this decision on how difficult directions to my actual location might be, especially if consciousness or communication might be an issue).
I also grabbed one of these from the local Home Hardware the other day on a whim, I'll test it out and let you know.