Placing a bulk crystal onto a sticky tape, folding and peeling the tape several times can create progressively thinner layers, eventually leading to a single-layer material, so-called 2D crystals.
If one considers the 2D crystals to be analogous to Lego blocks, those isolated atomic-scale Legos can be reassembled together as you want by using stacking techniques, which enable us to create novel hybrid structures that display totally new physics and unique functionality.
Here is an atomic Lego consisting of five different layers. Metallic electrodes were put on this Lego to probe its electronic properties.