Make one of these and you can carry a little bit of color wherever you go. It's super tiny and if you fill it with high pigment paints those tiny dots of paint can go a long way in a sketchbook (or two). Below the illustration is detailed instructions on how to make your own. My gift to you.

Altoid Watercolor Travel Kit:

Altoid SMALLS tin (sugarfree) is the right size and shape with NO EMBOSSING on the lid!
Press Sculpty of other polymer clay in the base of clean tin about 1/4-1/3 of an inch high.
Mints pressed into Scultpy form reservoirs. I can comfortably get 12 with the tiny square mints.
Bake according to clay instructions or around 270F for 15 minutes.
Wash out mints under warm running water. Dry.
Spray glaze on hardened Sculpty paint pans. Let Dry.
Tape to cover the sides of the lid and any other area that you do not want paint on. If you skip this step the lid will not close properly and scrap the spray paint and possibly get stuck.
White spray paint the lid. You want a few even coats followed by a glaze to make this surface smooth and durable.
Dry completely.
Fill reservoirs with the paints of your choice. I highly recommend artist grade paints if you can afford them.
Leave to dry a minimum of overnight longer is better.
Voila! When you use up the paint just refill it.