Septic TwistA strange combination of two strange ideas into one even more strange puzzle: Four layers in shapes of heptagons can be turned without jumbling and fudging.
Siamese Void PentagonsSecond variant out of a series of Holey Megaminx transformations. This one has two twistable faces left.
Six CubeAn edges only 3x3x3 in shape of a Burr Puzzle.
Sixcone 3x3x3 V1A 3x3x3 truncated with six intersecting cones in a shape closely resembling the Steinmetz solid.
Sixcone 3x3x3 V2A 3x3x3 truncated with six intersecting cones. This time resulting in a heavily concave solid.
Sixcylinder Megaminx V3Six cylinders joined in one solid. This time by extensions not truncations but with a different orientation.
Sphere In CubeCross between Rubik's Cube and Rubik's Sphere. Hand crafted mutation cube.
Spiral CubeA 3x3x3 which still has 6 sides but an additional twist. It lies somewhere between a 3x3x3 and a Fisher Cube.