If one novelty can be said to be the global symbol of the joke shop it is probably the plastic turd. A close second, and a much more palatable one, is the rubber chicken.

This model is not a little squeaky dog toy, this is a true rubber chicken, in all its strange deformed floppy glory. They measure a huge 50cm from beak to toe and we import them specially, which is more effort than it sounds.
 
Not suitable for children under 3 years. Choking hazard due to small parts.