What’s the worst or best customer service you ever received?

Was it in a supermarket, in a shop or getting information from a call centre about your bill or bank?Did they give you wrong infromation but later cause you to lose money or lead you to believe that there was no problem over what you requested only to find out they mislead you and you ended up losing out. For example: Phone up a my bank to ask for some information and advice. Later on in the week I went to one of bank's branches I was inform the information I was told over the phone was incorrect. It was so anoying and I was so upset I try to make a complaint and because I did not know the name of the person and the date and time, they told me that there is not a lot they can do. Now I always make of note of time and date and name of person.

what is the ideal customer service you receive? I was in the library and the lady was very helpful and went that extra mile to get all the information I needed.

Ideal - My opticians, SW ALLEN, they are great.