3x3x3 LLs2F L2LsFsThese two connected and additionally bandaged 3x3x3 implement two subgroups of the 3x3x3 at once.
4CubesFour parts (looking like a 3x3x3) connected into a single puzzle. The second (the other being an 11x11x11) collaboration of Tony Fisher with another designer.
4x6x7 (extended Siamese)This 4x6x7 is made just like a 3x4x5 (extended Siamese). It's based off of two 4x4x4s instead of two 3x3x3s.
Arch CubesTwo 3x3x3's fused into one puzzle creating a unusual Siamese-variant which is equivalent (solvingwise) to the Barbell Cube.
B12C111A twofold implementation of the slice cube group.
Bino CubeTwo Dino Cubes glued into a single puzzle.
Brams FortressEight cubes which outwards going faces twist connected to each other in sets of four faces.