Word / phrase: To take the piss

What does it mean? There are two main meanings. 1. when someone is joking and joking in an unkind way 2. when someone is taking advantage of someone or a situation.

Is it positive or negative? It has more negative meanings than positive. The context will be key to understanding which one is being used.  

When do you use it? If someone is always joking about something in an unkind way it can be used. It can also be used in your defence to show you're not being serious and just joking, and to show someone is taking advantage of you.

Example 1: We went to Bucharest for the weekend and he took the piss out of everything. It was embarrassing. 
Example 2: I called one department and then they told me to call another department, but then they told me to call the first department again. They must be taking the piss. 
Example 3: The taxi driver said it would cost £100 to get to the airport. What? It's only 15 minutes away. He's taking taking the piss. 
Example 4: Mate, I'm only taking in the piss, don't worry.


Question: When was the last time someone tried to take the piss?