As Like many others I saw the wyrmwood kickstarter and felt like making my own version of their organizer trays.
All pieces print without supports, and you'll need 1 base, 3 legs and a top for each tray.
Then you'll also need a cork coaster and 12 10x2 magnets... Or whatever you want to put in a 10mm x 3.4mm slot. Everything just then snaps together.
Make sure that the top legs holes are not aligned with the legs as the polarity of the magnets will prevent them from stacking otherwise. (my rendered pic is wrong)
Coasters (90mm diameter, 3.2mm thick) for bottom: https://www.amazon.com/gp/product/B075TGD8XM
10x2 Magnets: https://www.amazon.com/gp/product/B0753ZPBLQ
(these are actually 1.7mm thick and each slot takes 2, so you could also use 3mm thick ones)
4/30/2019: Added caster and jail tiles. Caster tile uses 4mm ball bearings. Also added a part the size of the cork coasters if you need to trim cork ones to fit or wish to print one.
The author hasn't provided the model origin yet.