One thing you may not know about the peoples of the pre-Columbian Andean region: they were fond of making pottery with exaggerated penises. These were often pipes or water vessels and forced the user to place his or her mouth on the gigantic penis.
Note: These may not be safe for your workplace–it’s pottery with huge erect penises. Your call.
That one was found here.
I found this one here.
Two more (found here):
I like these because they remind students that sexual humor (making pottery that forces someone to drink out of a penis, for instance) is not even close to being a modern invention. I’m sure there are lots of other interpretations–that this actually shows an obsession with the penis than indicates a patriarchal culture, that it was part of a cult of warrior potency, and so on–but I bet there was also a level of joking going on too.
In my google search for “Incan penis pottery,” I also came upon this image of an Incan fertility temple (found here):