The Most Expensive Free Drink Ever - 9:00 pm - 23-04-2008

Today I had my French Oral Exam, a thing which I had been dreading for weeks. This is not surprising really, considering that oral is my weakest of the four skills (others being aural, written and read). What is surprising, however, is how well it went.
It went well for everyone by the sounds of it, as it wasn’t long before we were at a bar in West Bridgford buying a celebratory drink.
I ordered a bottle of Sol and then was told to wait around before I received my change. Feeling slightly confused, I sat down and waited for the manager to appear.
When she did, I was informed that my £20 note was counterfeit. I was sceptical that she might simply be trying to con me out of twenty quid, but by contrasting it with a ‘real’ note, it was clear she was telling the truth. She then told me that she was legally obliged to keep the note to give it to the police. She produced a police document explaining it.
I was defeated, so let her have it. She agreed to let me have my drink for free.
So - did bottle of Sol cost me £20, was it free, or was it the most expensive free drink ever?