The efficient conversion of chemical energy into mechanical work by specialized biological nanomachines enables a wide range of functions in nature, ranging from intracellular transport to large-scale actuation by muscles. Through suitable interfaces, these motor proteins can be employed in synthetic nanodevices with applications in biosensing, self-assembly, and molecular-scale actuation. Here, we give a brief introduction to molecular motors, with an emphasis on motor proteins, describe the challenges in interfacing these bionanomachines with an artificial environment, and provide examples of emerging applications.