She looked as though she was enjoying her ride, as I believe most taxi passengers in Barcelona do. However, her driver probably didn't speak much English. Taxi drivers here rarely speak the international language of commerce and tourism. In all the years I have lived (and before that, travelled) here, I have only come across one Taxi driver who spoke English.
That's why I was surprised to come across a service company called Barcelona Taxi Tour, offering not only reserved airport pick-up and drop-off but a variety of tours provided by drivers with supposedly "perfect English." Tours include a Gaudí tour, a Moderism Architecture tour, an Olympic tour and a general tour called, "The Global View." According to the web site prices are agreed upon when you make your reservation but it's a safe bet that they don't fall into a back packer's budget. That's OK though, because the city's buses and metro are great - plus Barcelona is a really great place for walking!
If you are a visitor or new to the city and do need to catch a regular taxi, though, here is a little info for you. Barcelona's taxis are regulated by the local government. Aside from controlling rates, another thing is the look of the cab. For that reason Barcelona's taxis are always black and yellow vehicles. Usually they are compact cars but a few are minivans. They are almost always comfortable and air-conditioned.
In front of the airport, train station and bus stations there are special taxi lanes for collecting passengers. On the street, you can flag one down when the green light on top of the car is on. Tip the driver by rounding up slightly - local people do not usually tip more than a few cents or 1 or 2 euros. Although local taxi drivers are usually honest, to be extra safe ask for a receipt as the driver's information is printed on thses. Click here for current information about taxi fares.
Taxis are available anytime, although it can sometimes be a bit of a challenge to find a free one on weekends around 3, 4, 5 and 6 in the morning because of all the people pouring out of bars and discos. That may be why some people don't go home until 7, 8, 9, 10, 11...or later. ;-)