A simple dice carry case in the shape of a book. It holds the 7 standard RPG dice, has a small spot for 3-4 other dice, and the lid functions as a dice rolling tray (I used felt to line the lid). I've used 3x6mm magnets to keep mine closed, but the fit is pretty snug and would stay on in most circumstances without the magnets. You can always play with the scaling on the lid to get a better fit.

The spine can be embossed with your name or whatever you like and I've included 2 embossed lids (a D20 and the D&D logo (license WoTC)) and a blank lid in case you have your own design, just be sure to remix or upload as a make so that I can see the awesome stuff you do!

The entire print shown printed in under 5 hours (base ~3.5, lid ~1.5) with a 0.3mm layer height using Grey Inland PLA+ (color changes are Green Inland PLA and Yellow Inland PLA+).