These are computer-generated 3D models (left) and corresponding 2D projection microscopy images (right) of nanostructures self-assembled from synthetic DNA strands called DNA bricks. A master DNA brick collection defines a 25-nanometer cubic "molecular canvas" with 1000 voxels. By selecting subsets of bricks from this canvas, Ke et al. constructed a panel of 102 distinct shapes exhibiting sophisticated surface features as well as intricate interior cavities and tunnels. These nanostructures may enable diverse applications ranging from medicine to nanobiotechnology and electronics.