1) The taxi situation at Beijing Airport is a little worse. The taxi sharks are quite active at the international arrivals doors, come straight to the official taxi area after you come out. Official taxis have a taxi sign on the roof, and on the dashboard on the passenger side is a placard with the drivers registration number. If this placard is missing then avoid it. At your destination, you should requrst a fappiao (a receipt, which is generated by the meter). If the meter isn't working, you can refuse to pay, and if the driver threatens to call the police, encourage him to do so. At this point he will write a hand-written fappiao, but make sure he (or you) writes down the car registration and the driver registration before paying your mo for the taxi.
2) Please keep the adress card from your hotel or written by your hotel staff in Chinese to show the taxi driver. A hotel card with the Hotel's name in Chinese for your return trip. So always carry a card from the hotel in the event you get lost in the city. Shown the car to the driver and ask him to bring you there. Most of the drivers are not able to speak in English with exception of a few that is specially trained lately for the 2008 games.
3) You can also charter a taxi ( as a private your own car ) for day trips to the Great Wall ( which is around 1.5 hour drive from city) or just to transfer you around various locations like Forbidden City, Summer Palace, Temple of Heaven, Panjiayuan, Wangfujinging, etc. As long as it is within the city, most drivers are more than willing to let you charter their car for the day. A typical taxi will cost around RMB450 to RMB600 for an 8-hour day rental with driver. Each car can hold 4 comfortably. If you are sharing the car among 4, that is less than US$20 for a day.
4) Travlling around Beijing by taxi is quite easy. However, when it rains, it becomes a totally different situation. Keep in mind if you have a plane or train to catch, expecially if you have an unchangeable ticket! Firstly, cabs can be very difficult to find in the rain. Secondly, many taxis will simply refuse to take on longer journeys, especially to the airport and they also will refuse to go anywhere if it involves driving on the 3rd Ring Road which is jammed completely in the rain! So check the weather report and it is better to plan to get to the station or airport three hours before check-in time if your ticket is unchangeable.?
5) The bridge and road tolls will be paid by passengers. For a journey that takes longer than 10 kilo or running after 23:00, the fares will be charged at 50% more.