Tchotchke (Typically pronounced "CHACH-kee") are small toys, gewgaws, knickknacks, baubles, or trinkets. The term has a connotation of cheaper items or disposability, as well as tackiness, and has long been used in Jewish communities, most notably in New York City. It probably comes from an obsolete dialect Polish word czaczko, a trinket, knick-knack or ornament.
The word may also refer to items dispensed at trade shows, conventions, and similar large events. Also, stores that sell cheaper souvenirs in tourist areas are sometimes called "tchotchke shops."
Here at Jews for Jesus, we use the term to mean things that you might grab at the counter, some little trinket to give a grandchild or as a momento of your visit to a Jewish book shop in Australia. Some even buy these to give as 'favors' to give after Bat Mitzvahs and birthday parties.