Tchotke is a Yiddish word now relatively common in English. It literally refers to a rope with knots in it, used as a memory aid for prayer. When used in English, however, a tchotke or chot'ke is a free gimmick given away by a company for advertising purposes. Small foam brains with a logo on the side are tchotke, as are keychains, Magic: the Gathering cards, keycaps from old IBM Keyboards, useless hard drive platters, and slinkies.
Dot coms were particularly famous for handing out actually valuable tchotke. Most of them are gone now, but my closet full of frisbees, beach balls, bobbleheads, and the Kahuna Akamai remains.
a_scar_fairy has a collapsible Guiness frisbee.