Six-sided masonry bricks have been used since the time of the Pyramids. It's time for an "Improved Brick" that is easy to carry and assembles itself:
MakerBot Video - watch a video explaining the concept (starting at 1:53)
A tensioned "skin" is filled with polyhedrons for bearing compression force. In an uncompressed state, the polyhedrons are pourable like sand, salt or sugar. No hand labor is needed for assembling them into the skin: they automatically find their own orientation by following the skin's form. When compressed by tensioning the skin, the polyhedrons rigidly interlock. The skin filled tightly with polyhedrons provides a sturdy structure for a house, chair or the like. Later, the structure may be taken apart by releasing the skin tension and pouring out the polyhedrons. The lightweight skin may be CNC-cut to a computerized pattern (the way clothing is made); it folds for easy transport.