Plaka is maybe the most beautiful place in Athens by night. Between the narrow strairs, the restaurants and taberns put their tables and charis outside. There are people sitting outside, drinking their greek coffe or eating souvlaki, and you can hear live typical greek music. The atmosphere is just wonderful by night, with the perfect amount of light in background.
We were sitting in "Zorbas", and we had a great waiter. We talked a lot and I learned in 2 hours more greek than in the 10 days there. He also explained us what "Patagonia" means, the origin of the word "anorexia", and lot of other things.