DIY makeup storage ideas: Storing nail polish bottles on the wall

I don't like storing my nail polish bottles inside a cupboard, drawer or shelf - I would always be taking out all the bottles anyway to compare and contrast and finally decide. But keeping around 198 bottles spread out would mean I wouldn't have space to walk around.

I had always thought that those shelves you have inside some refrigerators would be great to store nail polish, provided you could hang them on the wall. I found some spare parts at a local repair shop and they were willing to let me have them for a steal. These are seen in older Panasonics, Kelvinators and Siemens refridgerators mostly. These measure 12'' by 4''. They are also quite sturdy, once fixed up with hooks, and hold around 25 bottles each.

I stuck in some thermocol on the bottom of each shelf because some of the minis or Konad specials could fall through. I now have eight of these shelves proudly affixed to my wall. Each carries colour-sorted nail polish bottles. One large shelf would need more wall space, whereas these can be hung separately on the wall. Getting nail polish out of these shelves is like reaching out and grabbing candy.
How do you sort and store your nail polish bottles?