I created this “simple” dice tower to truly roll all dice and completely randomize the outcome. Specifically, I made this because my wife obliterated me three games in a row with nearly perfect rolls while I failed nearly every roll. 

If we hadn't been using the same dice, I would've sworn she was cheating… :) 

This model has a lot of overhangs but in my experience no supports are needed. I used fuzzy skin on the outer layer just for fun. I tested with all the different dice sizes I have and I had no issues with clogs.