Make this 3D puzzle out of wood.
The Soma Cube wasinvented by Piet Hein in 1936 during a lecture on quantum mechanics conducted by Werner Heisenberg.

(taken from http://en.wikipedia.org/wiki/Soma_cube )

The cube is made from 27 cubelets formed into 7 pieces. I've used the naming convention used on wikipedia to make things easier to understand.

Step 1: Tools and Methods

Basic hand tools are all that's needed.

hand saw.
mitre box to keep all the cuts square.
some sort of clamp.
A wood workers try-square to check all cuts.

Select a length of wood batten, oak for example, and make sure its square. My wood was 29mm square and 1 meter long, even though I only used about 820mm.
Instead of cutting 27 accurate 29mm sq cubelets, I cheated and used only 15 cuts to create 2 X 3 segment pieces, 8 X 2 segment pieces and 5 individual pieces.
Ideally all the wood grain should be jumbled up to make it harder to analyze the complete cube, but using my shortcut method this wouldn't have been possible so I'Il make fake saw cuts to simulate individual pieces.

Step 2: The L Tetracube and Tricube

The L tetracube was made from a single piece glued to a 3 segment piece as can be seen from the grain in the pic below.
The L tricube was made from a single piece glued to a 2 segment piece.

Step 3: The Left Screw and Right Screw Tetracubes

These two should mirror each other, otherwise its wrong. I used 2 x 2segments to create these ones, make them at the same time to get it right.

Step 4: The T Tetracube

A single piece joined to a 3 segment piece, again with fake saw cuts about 5mm in depth to simulate individual pieces.

Step 5: The S Tetracube

This is a simple one, two 2 segment pieces joined and fake saw cuts.

Step 6: The Branch Tetracube

This one is the trickiest to get lined up and square, start with the L tricube shape and when dry glue on the final single piece.

Step 7: Some Thoughts and Somazims

There are plenty of Soma cube web sites on the internet, my first stop was Thorleif's SOMA page here. http://www.fam-bundgaard.dk/SOMA/SOMA.HTM

I find the easiest way to solve a somazims is to unhinge the everyday mind and let your hands run free, trying various things till eventually you reach the epiphany moment.

Taken from Wikipedia
An epiphanyis the sudden realization or comprehension of the (larger) essence or meaning of something. The term is used in either a philosophical or literal sense to signify that the claimant has found the last piece of the puzzle and now sees the whole picture."

Some somazims presented for starters.