Macromolecules make up the fabric of life. Without the protein machinery and DNA/RNA as information carriers, no cell would be able to complete its life cycle and to remain in a non-equilibrium thermodynamical state. Looking beyond the chemical structure of proteins and DNA, it becomes clear that their intricate interactions with other macromolecules form the core of their functionality. In DNA, this is evident in the formation of the double helix through H-bonding, whereas in proteins, numerous examples of functional macromolecular assemblies exist. A particularly impressive example of such a macromolecular assembly is the photosystem I,1 which is a trimeric complex forming a large disc (Figure 2.1). However, each complex is an assembly of a dozen proteins, bringing together and precisely positioning hundreds of co-factors (chlorophyll). An equally impressive example of cellular machinery based on macromolecules is the ribosome complex, where RNA read-out and protein synthesis take place (Figure 2.1).2 It is beyond the scope of this chapter to discuss the exact mechanisms of assembly and function, but these examples do illustrate the tremendous potential of polymers in nanotechnology, if, at least, we learn to harness such systems in man-made devices. A first step towards harnessing the power of biological ‘machines’ has been demonstrated by the seminal work of Montemagno and co-workers.3 By engineering a biomolecular nanomotor F1—adenosine triphosphate synthase (F1-ATPase) and integrating this biomolecule into an inorganic nanoscale system, they demonstrated the feasibility of building a nanomechanical device powered by a biomolecular motor.