Alex,
What would you take with you I wonder?
In my view, there are so many factors that decide what to take and where to go with who. Availability of the stuff you already have and availability of the stuff you can find an/or scavange. You cannot find trash in prestine wilderness as good as in (semi) urban surroundings.
Also something that suprises me is the social aspect many people forget when wondering about this question. The classical fact that "you know everybody in the world in 5 to 7 social steps" is a crucial element.
This is about the with who would you go question. I would realy like to stay with my girlfriend for example. But, she and I would also like to be with our families. Those families contain brothers and sisters with boyfriends, girlfriend, wives, husbands and friend. Not to mention that living out for an extended period of time will go a lot smoother in my opinion with bushcraft/survival buddies of mine.
So if you could take everybody you wanted with you. And those people could do the same. Then with knowledge of knowing the world in 7 social steps, we would be at a secret location somewhere deep in the forest dodging groups of savages with about 6 milion people.
your thoughts?
edit:
The absolute bare minimum would be bare naked chasing around fish in a river at some subtropical location whilst holding on on your just found coconuts
OK, here goes:
1) My old Canadian Forces duffle bag for carrying what I need or scavenge. It's old(yet still thoroughly servicable)and looks it. It doesn't look like much of a 'prize' for people looking to steal things. It has straps to carry by hand, straps to be worn like a rucksack, or a sholder strap to be worn like a bandolier.
2) My old Canadian Forces haversack. Same condition and innocuous appearance as my dufflebag. Here's where I keep my absolute essentials.
3)Clothing. Depends on what time of the year we are talking about. It can get really chilly here in Canada in the winter.
That being said: Shirt, fleece or wool sweater,overcoat, PVC poncho, 1 summer weight socks, one winter weight socks,well broken in pair of hiking boots(mine are 14 years old -and look it- but are still perfectly good) boots or shoes BTW are one of the first things 'lifted' from you if you've ever been in a homeless shelter, and I imagine the same applies in a societal collapse, cap/hat of your choice, gloves( I have old dearskin ones that look rough but do for work and warmth in a pinch).
4) 2 wool blankets-for same reason mentioned by others
5) PVC poncho(mentioned under clothing), but one should think of any discarded non permiable plastic sheeting that one scrounges, can double as poncho/improvised shelter.
6) Tarp-obvious reasons.
7) Water container, many types to choose from.
8) Metal pot- cookcraft.
9) Firesteel/flint&steel, whatever your preference is. Cheap disposable lighter.
10) Good full tang knife, good folding pocket knife, small/micro hatchet, foldable/collapsable saw
11) Hiking/walking stick-many uses.
12) Candles-heating in a pinch, light, potentially slow cooking/boiling
13) Basic first aid kit
14) Most importantly, the knowledge to make any of the above mentioned.
Thats it for now, off to the salt mines...oops work that is...
Cheers
Alex
7)
) is the mother of invention so perhaps.... I'm looking for a decent water proof hat without ventilation holes at the moment as a friend last time I was out camping boiled water and some burdock roots in his hat he saw it on TV somewhere! 
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