When you get a taxi at Rome's Airport
check if its a taxi of Fiumicino or a taxi of Rome because you will find a surprise at the end of the ride if get the wrong one.
Taxi's of Rome have a special fix price
of 40,00 Euros if your hotel
is in the ancient city walls.
Taxi's of Fiumicino dont have this fix price
and they would charge about 60/70 euros for the same ride. So pay attention or ask to the taxi driver before getting on the car! It happened to me that I live in Rome.