Thanks for the suggestions. I am looking for something to put in small kits for a few fluids: chlorine bleach, hydrogen peroxide, maybe isopropyl. I like the idea of Nalgene brand because they appear to be impervious to almost any liquid.

This one looks pretty cool:

http://www.amazon.com/Nalgene-Dropper-Bo...8591&sr=1-1

It looks tiny: 4ml, about 1/4 tsp. I think I now prefer the screw cap to protect the dropper.

I may look at some other bottles that already have stuff in them, but would need to thoroughly test them before trusting them to be rugged enough.

David