Many cities I have visited have open topped double deck tour buses. I always take advantage of these photo platforms both to get shots and to make a note of areas that I want to return to for later shooting...
Hong Kong was really nice since there was only my wife and I and another couple on the top deck. I could easily switch sides when a good photo opportunity was visible...
The standard double decked trolleys in Hong Kong are efficient and cheap methods of transport as well as good for an occasional shot.
However in Istanbul, the bus was filled and the best images always seemed like they would appear on the opposite side. I wanted to take the trip a second time and sit on the opposite side but my wife wasn't willing to do that...
I was very disappointed when my wife booked a tour bus in Athens and it was an enclosed air conditioned bus with no shooting possibility.