I was trying to decide what I should include in a kit that is to be carried with you, but not nessesarily on you. (for instance, aviation, boating, long car trips...)

One of the questions was "what should I put it in?" and right away I thought of the M3 Medic Bag I bought recently.

As far as I know, it's water resistant (the material feels like it, and there is a rain cover to protect the zippers, although that will probably not help much in immersion) and it has 3 seperate sections- one large, two smaller. This, to me, is pretty convenient- you can go directly to what you need without having to dig through the stuff you don't. Any of the sections would provide enough room for a complete "pocket" or belt sized personal survival kit easily, as well as first aid kit of decent substance. The large section could fit survival rations, water packets/containers, and so forth.

What do you guys use for your more extensive projects? I suppose a mini alice pack would work too...

Your problem seems to be a matter of terminology. A PSK is a pocket survival kit. It is designed to be carried in the pocket so that you have it on you at all times. What you are talking about is a maxi kit A larger more extensive supply of gear. The difference you very well may be come seperated from your other gear but a pocket kit carries the bare minimum but is always with you.

Here are some definitions that may help clarify the difference in kits by size.

Micro: About the size of an old fashion pocket watch or smaller. These are usually job specific. Fire, water, fishing, ETC. The design is for these kits to be scattered around your person or gear to be combined to form a survival kit. The ultra small [micro] size makes for compact storage.

Mini: The size is to fit conveniently in a pocket. This should be a daily carry item. The standard is usually based on the Altoid tin. This is the true stand-alone survival kit. These kits try to meet the minimum needs in most situations. This can be made up of several micro kits. Also called PSK's or Pocket Survival Kits.

Maxi: The next step up in size and level of convenience. Usually from the size of a large paperback book to a hard bound one. This is where shelter material is starting to be added. You step up to this when you are planing to leave the beaten path.

Pack: This is the size of a butt or daypack. This is where you start adding food for several days. Such as a 72 hour kit. Usually combined with full camping gear. Carry this for short side trips or even if just going over there. If you go out of sight of the main camp you may need it.

Large: This is your camping gear and supplies for and extended trip out and beyond.

BOB: The whole enchilada. This is can be everything up to and may include the kitchen sink. This is the get out of town or get back home kit. Usually transported by vehicle but portions are person or persons portable. Usually a large backpack or duffel. Although it can range up to a packed trailer, fully stocked pop up travel trailer or even a RV.

Raspy,
good post. Here are a few others

PSK - personal/pocket surival kit. Small tin or plastic container packet with survival items. Designed to be on person at all times.

FAK - First Aid Kit. No explanation needed.

SAK - Swiss Army Knife. Otherwise known as the Victorinox. If you looking for a pen knife these are as good as they get (personal opinion*)

ratpack - abbreviation for rationpack.

Reinhardt

Consider a few Eagle Creek shoulder bags:

Guide Bag - http://www.eaglecreek.com/40242.html

Vagabond - http://www.eaglecreek.com/40241.html

I use the Guide Bag. The Vagabond is a little bigger.

Another term is EDC - but I almost always refer to it as Every Day Crap...

Rena

I have two large kits. One in each car. The one in my wifes truck is designed to stay there in or very close to the car. It is housed in a plastic toolbox-type container. The other kit (my largest) is in my truck and is designed to be quite portable and serve as both a kit for my car as well a BOB to support the entire family. It is housed in a standard size day pack.

I apologise for the mis use of the term