Do you know who your best customers are? Do they know that you know?
I went to a favorite restaurant of mine last week. I go in about once a week to order a salad that I probably pay too much for - but it's a good salad. Anyway - after I ate my salad I decided I wanted a cup of coffee. When I went up front to pay the cashier called me by my first name and said it was on the house.
To my knowledge I had never told the cashier my name. Regardless, I felt special and they have a customer for life - all over a cup of coffee.