Paris limits the number of its urban taxis, thereby creating a shortage of supply and driving all the prices up and the customers nuts. Not surprinsingly, all taxi drivers zip around in Mercedes. During the day, the Metro competes harshly with the 4-wheeled official cartel but if you are wandering in the streets of the City of Lights after 1am, you are on your own in a jungle of scarce drivers who will refuse to take you on if you are not going far enough for them to make the ride worthwhile!

Singapore has a free and open system. The longest I ever waited for a taxi was 4 minutes. Rides are cheap, drivers are courteous and knowledgeable. They drive well, ask you to buckle up, respect their load allowance and give way to pedestrians. And some of them also drive a Mercedes. In a city where owning a car must set you back a gzillion $$.
For an extra 1.5 euros, you can call ahead and reserve in advance. The central reservation system has a positioning system, based on the signal transmitted by your satellite mobile phone and a synthesized voice whispers to your ear: "You are located at 43 Holland Drive - you will be picked up in 2 minutes".