Although Singapore is a small country and well connected by trains and buses, the most convenient mode of transportation is taxi.  It also happens to be the most expensive.  The flag-down of S$2.80 is comparable to taxis in Hong Kong and Malaysia but what makes it painful is all the surcharges.  Peak-hour surcharge is 35% of the metered fare, surcharge for pick-up in the central business district area and airport is extra, booking fee is according to the time of call.  When all the surcharges are added up, the fare may cost more than 3 meals in the local foodcourt.  I found this really neat website that calculates the fare and gives you an idea of how much to expect.