Moon, moonlighting is what happens when residents and fellows decide to work extra ER shifts apart from their normal duties in order to supplement their income. In most, if not all, the states, only residents are allowed to moonlight and in some states, only after they have completed at least their internship. This is also subject to rules that each individual hospital makes for its residents and fellows as well. Medical students cannot moonlight to make extra money. We would neither have the experience nor licensure prerequisites to moonlight. At the most, med students may be able to work in a lab to make some money.