OK long term listener first time caller, if you get my drift.
This is my attempt at coming up with a sensibly sized survival kit. Its not the biggest and its not the smallest. It's probably a 3rd bigger then an Altoids tin. I did cheat !!!! I bought a pre made survival kit and augmented it (all items were cheaper this way)

Step 1:

This kit started out as 2 individual items, the pre bought kit pictured and a disney cars mini lunch box. I didn't do much to the pre made kit except leave some items out like the pencil and paper, but for the disney tin.... yeah it needed work!
First it came with this little handle which is cute for a 4 yr old but would catch on stuff for me and well look plain silly so using my leatherman I unbent the metal tabs inside holding the handle on and got rid of that. Well that leaves me with 2 small problems in the shape of the 2 holes (sorry I didn't take picks of this I was unaware of Instructables at the time). Using some quick steel putty I plugged the holes, thats what those grey/greenish blobs are on the inside.
Next the bottom was like a lid pushed on with 4 rivets holding it but I could see daylight between the 2 so out came the silicone sealer . I smushed a bunch in and around the perimiter of the bottom. I'm not Guaranteeing total waterproofness but it should keep the worst out.
Next I sanded the outside and sprayed it with a can of black paint.
and thats the tin.
its 4 3/16th" wide by 1.5" deep

Step 2: Contents- the Nitty Gritty.

ok the whole yellow box mouse points isnt working so ill just list the contents here from left to right.
1) 2 2x2 gauze useful for cuts definatly not much use for major medical issues.
2) a roll of duct tape wont even explain those!!
3) triple antibiotic ointment normally have more but I used a couple recently
4) a roll of nylon thread, sewing fishing surgery
5) Swedish fire steel and striker- makes lots of sparks even lighting damp tinder (with a little luck)and they last ages.
6)Signal Mirror, Rescue Flash" with aiming hole for signaling for rescue.
7)chap stick- your alone, your lost and your lips really hurt, well you can deal with one of those right away. Its a comfort thing , personal choice.
8)Spark-Lite" Fire Starter works one handed and is small came with the pre made kit.
9)(second row left) butterfly stitches
10) aluminum foil folded up- boil water in it, make fishing lures.
11)compass - needs no explaining.
12) fishing line- wrapped around a bobbin allows you to carry lots of it in a small neat package, cant remember what break strain but pretty heavy, fishing, snares, traps.
13)photon led light useful, it has 2 brightness settings and a flash setting its very bright.
14)Whistle, Rescue Howler" - pea less design, very loud with 3 notes simultaneously used for signaling.
15) yellow masons twine- this was a replacement for the cordage in the pre made kit which had white stuff like kite string. Masons twine is very strong (250lbs breaking I think) its also abrasion resistant, not as useful as Para cord which I always have on my person anyway but lighter and less bulk.
16)4x Tinder Quick" Fire starter very useful to carry dry tinder with you, this will light even when wet just pull apart to fluff up, dont always need the whole piece- more expensive then cotton balls and petroleum jelly but not as messy.
17)proper glass magnifying lense from a set of binoculars - fire starting pulling splinters.
18)(bottom row left) 2 scalpel blades, make shift knifes, arrows, surgery, skinning and so on.
19)very thin magnifying glass- plastic yes I know I already have one but it came with the pre made kit and takes up as close to zero space as you can get so why not after all glass is known to break.
20)mini sewing kit got from a hotel once, all sorts of uses, contains another needle.
21) fishing tackle- split shot, bunch of hooks, some snap swivels all in the little container, next to it a spoon and a 3 way swivel not just for fish, bait it for birds too!
22) a couple of needles, one has a very large eye and is thick
23) wire- all sorts of uses, snares and repairs come to mind.
24) jigsaw blades one for wood one for metal. For fine cutting and shaping , notching for traps or making repairs and modifying stuff, also strike flints really good too, saves your knife!!

Step 3: Summery

I take this kit hiking, hunting and it sits in the carif im not actually out in the outdoors, when ever I do go out I allways have at least a pocket knife and leatherman wave normally though ill have a mag light, and also a sheath knife too and a paracord bracelet,and a lighter.
Here is the list of parts from the pre made kit:
1..... Signal Mirror, Rescue Flash"
1..... Spark-Lite" Fire Starter
4..... Tinder Quick" Firestarter
1..... Whistle, Rescue Howler"
1..... Waterproof Survival Instructions
1..... Duct Tape, 2" x 26"
1..... Scalpel with Handle, Sterile, Disposable, #22 Blade
1..... Compass, Button, Liquid Filled
1..... Aluminum Foil, Heavy Duty, 3 Sq. Ft.
1..... Waterproof Paper
1..... Fresnel Magnifier
6..... Safety Wire, Stainless Steel, (6 ft of 0.020")
1..... Sewing Thread, Bobbin #69, Nylon
10.... Nylon Cord, #18, Braided, (10 ft. 100lb test)
1..... Sewing Needle, #18, Chenille
4..... Fish Hook, #10
2..... Split Shot, Lead B
1..... Snap Swivel, Size 12
1..... Pencil
1..... Pocket Survival Pak Contents List
4..... Safety Pins (normmaly in the kit but had used them for something)
I know Ill take plenty critisism for my choices, everyone has very personal ideas of what should be in it.
I have tried to go for a kit with plenty back up like 2 flint striker and 2 magnifing lenses ,I belive that out in a serious situation something breaks , it dosnt hurt to have a back up so yeah plenty of redundancy in my kit
let me know what you think :)

Step 4: Some Tools I Carry

I dont always carry all of these I tend to swap them in and out as I feel like it. If Im going for a while ill pack extra like the folding chain saw.
the big pick of knives from left to right are:
1) Buck- I dont know the name but I bought it at ll Bean in maine for $20.00 its a great sized knife and comes pretty sharp.
2) Cold steel Canadian belt knife- with shipping $20.00 from Smokey mountain knife works online- the factory edge on this knife truly is RAZOR sharp and it holds an edge for ages, unbeatable quality and crazy price!!!!
3) a cheap Winchester I keep it as it has a thick spine, full tang, wooden scales ,its a pretty decent quality and was under $20.00 at Wal-Mart, nice weight to it too.
4) cheapy off Amazon has a nice shaped blade, comes with a decent edge on it and the blade has some kind of coating on almost like pick up bed liner, its weighty and takes a beating. Price ? I think under 20 bucks incl s&h
5) a small leatherman I sometimes carry instead of my wave for weight purposes.
6) lastly Id like to introduce the cara cara, its made by byrd a Chinese company under supervision and quality control from........ spyderco!!!!! who also back it with a one year guarantee, this model was around 25 bucks incl s&h. Great steel at a great price with great quality. I carry the meadow lark plain edge which is a bit smaller as an everyday carry (see other pick)
then up top is the folding chainsaw from Winchester.
The other pick is what I carry on a day to day basis-out in the woods or at home. comprises of leatherman wave, 2 aa maglite 3watt led and byrd made meadow lark in plain edge.