I tried a few other designs for holding paint bottles for crafts and models and I found that none of them really met my needs. So I designed some myself. There are holders for three sizes of bottles, 17ml (vallejo), 30ml (similar to the 17ml but thicker), and 60ml (vallejo bottles or folk art, etc.). Each of them comes in 2, 4, 6, and 8 bottle holders. They can be used as desktop paint racks, or mounted on a wall as each has screw holes in it.

If you'd like different sizes or quantities, let me know and I can create one.