I use the same containers for meds. Twelve containers can be carried in a shotgun ammo pouch (e.g., http://www.cheaperthandirt.com/ZWB135-403-2159.html ). One cannot use all of the large size containers in the pouch—I use 4 of the larger and two of the smaller containers on each side of the pouch referenced.

Thanks for all of the ideas, I think I am going to start with a few of the 5/16-7/8 travel containers and put them in one of those pouches that hold shotgun shells. Maybe one that has the webbing inside that holds the shells. I think it would be about the right size. I also like the idea of the mini-zip lock bags, in a hard case all labeled.

For my PSK I just keep them in a mini-altoids tin (both practical and amusing), but for my FAK I've taken one of those 7 day pill containers and printed up labels for each compartment outlining what the pills are, what it's for, the dosage, and expiration date.

For example, one reads:

Ranitidine
Acid Reducer
75mg
2008 MR

...Since my kit itself is sufficiently water-tight, it works quite nicely.

Plano makes a bunch of small tackle boxes for fishing weights etc. that are very small and with many pill sized compartments.

I use the small Plano boxes as well. They also make great battery carriers for AA and AAA batteries.

Might be a bit tough to find, but 35mm film cases would probably work fine.

As an aside, if you drill a hole in the bottom, you can use one to keep the mouthpiece clean on your hydration-bladder.

I have used ...with success ... those travel size pain reliever bottles. My last ..even smaller bottles are old contact lense bottles. When I get new one they come in a little glass bottle with a plastic clip to hold the lens suspended in a solution. I remove the clippy thing, clean them out and peel off the labels.
My smaller pills, I can store 30 doses. Not as small ones I can store 14 doses. Last trip to the Eye doctor I asked for and got 4 more bottles. This year I'll ask again ...as I have found more places to stash my meds (at work, in my car, in my travel shave kits for business trips, my EDC and BOB for starters)
After Katrina, I decided I needed to have at least a months supply of my meds in at least one of my kits.
The travel size pain reliver bottles work better for bigger pills and 10-14 doses are able to fit ...which is a reasonable number for most applications....and NOT all brands are the same size...some are fatter than others. The Aleve and Advil ones are the skinniest I think. So I get 2, put all the pills in one of 'em for my FAK and use the other for meds.
The contact lens vials are glass ... so they could be broken...but you'd have to work at it. I also have a few that are plastic, but they are smaller yet ..but 14 days of 81 mg aspirin fits no problem.

Here is what I use. It has locking lids. Biggest drawback is that it is not waterproof. Each is labeled with name, dose, and what it treats.

I use one of these:

http://www.organize-everything.com/dosipiboxwih.html

It's not water-tight, so it should be stored in a plastic bag, but it has a lot of compartments of various sizes, and is overall about the size of an Altoids tin. Not quite small enough for a pocket-size kit, but well-suited to a vehicle or travel kit.

I got mine at WalMart for about $1 each a couple of years ago, but I can't find them there any more, at least not at my local store.

I use Glad Press N' Seal.

You drop your pills on a piece, fold it over, create the seal by running your fingers around the pills. Trim the excess. Done!