Here's another: At first glance, it might seem strange for an apartment building to advertise a "shut" until you figure out that they mean a "chute" (and it's pronounced correctly as well) to dispose of your trash.
Another sign I wasn't able to photograph said "Respect the..." followed by a picture of a zebra. As it turns out, in Bogota zebra doesn't only mean a striped animal that you see at the zoo; it also is used to mean "crosswalk" for pedestrians. (In the US we have that sign that reads "Don't Block the Box" which, unless you can figure out that it also refers to crosswalks, could be equally confusing for non-English speakers. The sign is usually accompanied by a drawing but it's not necessarily clear at first glance what it's referring to.)
See my webpage on Colombia at http://www.latinandcaribbeantravel.com/colombia.html