Nestor Games
Domino Tower

Domino Tower is a classic Oskar puzzle. Each of the four identical parts can be thought of
a set of domino pieces glued together. That was how the original prototype was made.
The version by Nestorgames is 3D printed at a surprisingly affordable price.
https://nestorgames.com/#dominotower_detail
Trisected Cube

Cubic Trisection was first shown to George Miller by Robert Reid as part of his box of all the ways a cube could be trisected by three equal parts. George asked Oskar van Deventer to design it. Most people have a difficult time putting it together. They usually try and force the pieces to "snap" together, whereas they easily glide together when twisted along the main diagonal.
https://nestorgames.com/#trisectedcube_detail


Transmission

Transmission was Oskar's exchange puzzle at the International Puzzle Party in Helsinki, August 2005. This is a new edition.

The object of this puzzle is to place the four gears onto the four axles.
If you place them randomly, most likely the gears will jam and do not turn.
In the solved state, the four gears can spin smoothly.
You can buy it here.