Nanny cam technology varies from model to model. There are a number of nanny cams on the market that are as small as a battery, while other cameras can be hidden inside a pen. Specialized shops sell a wide variety of hidden cameras that are adaptable enough to be used in any way the purchaser sees fit. Hidden camera equipment can differ in price from 10 dollars for old models bought secondhand, to thousands of dollars for state of the art technology that includes a monitor and other accessories. Many people believe that this boom in nanny cam technology started off with famous words: Smile, You’re on Candid Camera. Fans of the famous TV program Candid Camera were among the first consumers to realize that nanny cams could be used for purposes other than security and surveillance, and people started to understand the potential that this technology offers.