1x1x4A stupid cuboid built just for the sake of completeness.
4x4x5The first mass-produced 4x4x5.
4x4x6A fully functional and fully proportional 4x4x6 made from a 4x4x4.
4x5x5The first mass-produced 4x5x5.
Case CubeAn extended version of the "Octagon/Cube"
CheeseAnthony Greenhill's 2-layered Cheese created from a UFO mechanism.
Circle MinxThe fist application of the circle-concept to a megaminx.
Constrained CubeA 3x3x3 which twisting abilities can be contrained by various pieces. Mass produced versions of four variants exists.