I needed something to hold my paints for painting miniatures. I saw a couple on Thingiverse, but wanted to make my own. While I was at it I made a few variations on the theme holding 3 up to 15 (if you have a big enough bed).
Easily holds Army Painter, and Reaper dropper bottle paints. Doesn't hold Citadel paints though.
** Edit: I added a 4 and 8 slot holder for Citadel style paint pots. I mostly use Reaper, but I like the shades from Citadel. So, I made some matching paint holders for those. I only did 4, and 8, so if anyone wants bigger sizes let me know. I only have a few of Citadel right now.