What appear under an atomic force microscope to be tiny rings with little bits missing are actually nanoscopic rings made of double-stranded DNA with a little gap in the form of a short single-stranded fragment. As Michael Famulok and his team from the University of Bonn, Germany, explain in the journal Angewandte Chemie, this gap is a place to attach other molecules that have the potential to transform the rings into versatile nanocomposites for various applications.