Hello,
I have just finished to print out a 3D Cube Puzzle with a FABLAB's 3D printer.
Pieces are made from different colors so the cube looks nicer and those Tetris like shapes are quite cool.
Here are the pieces:
And the cube assembled:
You can find the sources on GRABCAD here: Cube Puzzle.
This community got some pretty good models that were engineered for 3D printers.
Regards.