The Soma cube is a mathematical puzzle by Piet Hein. Seven pieces made out of unit cubes must be assembled into a 3x3 cube. The pieces can also be used to make a variety of other interesting 3d shapes.

The soma cube is often regarded as the 3d equivalent of tangrams.

The seven soma pieces are:

The bent trimino
T: a row of three blocks with one added below the center
L: a row of three blocks with one added below the left side
S: bent trimino with block placed on outside of clockwise side
Left screw: unit cube placed on top of anticlockwise side. Chiral in 3D.
Right screw: unit cube placed on top of clockwise side. Chiral in 3D.
Branch: unit cube placed on bend. Not chiral in 3D.