The drop swindle was a confidence trick commonly used during the 19th and 20th centuries.
Employing a variety of techniques the con usually consists of the "dropper", who purposely drops a wallet containing counterfeit money near a potential victim.
One of the leading practitioners of this confidence trick was "Kid Dropper" Nathan Kaplan, an early twentieth century gangster.
While the drop swindle is now fairly well known it is still practiced today as most major cities receive complaints regarding this specific scam.
Variations of this confidence trick are seen in movies like The Flim-Flam Man (1969), The Sting (1973) and Matchstick Men (2003).