A space filling shape is a shape which when stacked appropriately will completely fill the space without voids. It could be possible to build any type of structure provided these shapes were small enough and you had a large number of them.
2D net patter cut out with a 2D plotter with swivel knife attachment.
Double sided tape applied to the tabs works best.
My new plotter cutter is handy for cutting many 2D shapes from a variety of materials.