Bangkok has a lot of traffic. It is easy to sit in traffic for a long time. Even the lights can take several minutes to change.
I remember when I was here in 1989, I took a taxi or bus to the airport (I don't really remember the details), and it seemed to take a very long time. It must have been in October, and I remember the weather being hot, and us being stuck in traffic.
Now Bangkok has a wonderful rail network (I think they did not have it in 1989), including a fast and efficient rail link to the airport. There are still many places rail doesn't go, however.
Bangkok also has lots of canals. Some of these canals have passenger boats that work a bit like buses. They are quite fast (no traffic), and even though the canals don't exactly smell good, I find them fun to ride.
Because it sometimes rains (a lot!) in Bangkok, and also for protection from the hot sun, the boats are covered with a thick grey tarp. On the sides of the boat is a light blue tarp, which is connected to weights by ropes through pulleys, so the passengers can pull the tarp up and down.
The tarps on the side might be needed when it rains, but most especially they are needed when there is another canal boat, which goes fast enough to cause a lot of spray.
As well as going on the canals (called khlong in Thai), I got to take a boat on the Chao Praya river, the main river through Bangkok.
The Chao Praya flooded last year and caused all sorts of problems, though because it was predicted well in advance, caused relatively few casualties -- according to wikipedia, 506 deaths and 2 missing persons out of 3 million people affected. For comparsion, Hurricane Katrina may have killed over 1,800 people.
Anyway, the Chao Praya is very well behaved now.
The boats with an engine mounted high in the back, and a long shaft down to a shallow propeller, are very characteristic. The propeller is often close enough to the surface of the water to cause quite a splash, though the boats themselves are not very fast (the khlong boats may be faster). I suppose the shallow propeller is good for shallow water. The shaft and propeller can be lifted out of the water.