Sapo - Sapear

Literally, sapo is spanish for toad (or frog). But as always, in Chile it has yet another meaning.

Sapo (noun) - a person that is 'nosy' and trying to find out what is happening or what people are saying.
- Juan tiene fama de ser sapo por siempre preguntar demasiado.

Sapear (verb) - the action of being nosy. Sometimes it means to eavesdrop.
- Mi vecina siempre está sapeando.

Another meaning.
Sapo (noun) - Sometimes when you are travelling by bus in Santiago, you will see a man (that is usually standing in the middle of the street) shout some numbers at the driver, who will in turn give him a coin or two. The numbers that he shouts are in fact the number of minutes that have gone by since the last bus from the same busline or going along the same route. These men are called Sapos and earn a living (though illegally since it's not permitted for tax reasons) by writing down the time every bus goes by that part of the street and calling out the numbers to them.

Why do they do it?
So that the driver knows whether there is a bus a short distance ahead that could be taking any potential clients. If there is, they will usually speed up to try and overtake it. In Chile, the bus drivers don't receive a fixed salary. They receive a small percentage of every passenger they take, hence the race against time and other buses.
Tambien está el dicho:

Muere de viejo y no de sapo.

En otras palabras, no husmees tanto en la vida de los demás.
Sapo (noun) - Sometimes when you are travelling by bus in Santiago, you will see a man (that is usually standing in the middle of the street) shout some numbers at the driver, who will in turn give him a coin or two.

Interesante. En el Perú les llamamos "dateros". Esto viene de "datear" o "pasar el dato", que significa informar. El término "sapo" se emplea exactamente igual que en la primera acepción mencionada (mirón, curioso).

Saludos,

Raúl