Henry Segerman is a mathematician who likes to help visualize mathematical principles using 3D printing. He has a book that pairs the ideas and topics with 3D objects you can print out.

His YouTube channel covers an amazing number of topics. Different kinds of irregular dice (slant, skew, dLX, wild d6’s, and others) that are fair but look very different than the standard regular polyhedral style dice. He makes interesting puzzles, visualizing 3D printed objects of higher dimensions, impossible geometry, interesting gearing, topology, and many other cool topics.

What’s great about his channel is that he’s a mathematician so you get a healthy dose of the theory that makes the objects possible.