The labor involved in creating these boards means that they can't really be produced economically at scale. They can be created for fun and sold for what amounts to $10 or $20 an hour of labor. More importantly, they can be meticulously designed and built, and then shown off on the internet, and that's enough to create a DIY craze. Specifically, the folks at LumberJocks.com are contributing hugely to the work.
Here we'll look at only what's referred to as "3D" cutting boards, which is to say that the design of the board, specifically the wood species selection and alternate color placement, is planned such that the board exhibits a striking multidimensional, illusory, or raised-surface visual effect.
Some of these are veneered or otherwise are more suitable as serving boards than end grain working chopping blocks. Still beautiful.
Here's a selection of some of the nicer boards from Lumberjocks, each one credited to its builder.
Impossible #3 by lumberdustjohn.
Piano keys by JL7. Highly niche, but still interesting.
Cube-in-a-cube style from SPalm.
Nested boxes by lizardhead.
Large blocks by Tag84.
Cubies by SPalm.
This one by Jim Sellers is compelling, but the round shape is a hard sell for me. He's using veneers, plus puttying and coloring the voids in black.
Tumbling block by jasondain.
Inversions by jadams.
Cubicle style by degoose.
Chevron steps by Spalm.
Escher by jeepturner.
I'm undecided on this "bulge effect" look, here pictured by caocian. It's certainly interesting, and the creator's tagline "Help me, I can't stop" is a great summation of the cutting board craze. Beyond 3D, this almost looks 4D; as if you could chop onions too close to the center and they would collapse into the board's event horizon and be forever irretrievable. On the other hand, it's a bit unsettling to look at. I think it might be confusing to cut food to uniform size against the reference of a non-uniform or even intentionally illusory surface.
For boards that will receive daily use in a kitchen, what's really important is that the board does not sit flush against the countertop, so that it can't warp from standing water. Hefty plastic bumpers at the corners are key here. Boards must also be sanded and oiled every six months.