A nice pyramid of cubes was modeled and rendered by David Pearson (fpsurgeon). Each lower level of the pyramid consists of smaller cubes, which are four times more than above. So we see a simple but elegant fractal. This nice rendering was created as a further development of studing by author an open source program Structure Synth, which provides creating 3D structures from a set of user rules. One of preliminary studies you can see below.
Imagine if the top cube of the pyramid is too heavy, and the whole structure will collapse.