The Singapore metro (called the MRT) is probably the most efficient public transport system I have ever used. A couple of weeks ago somebody sprayed graffiti on one of its trains, seen in this clip. This is unheard of in squeaky-clean, conformist, authoritarian Singapore, and has caused national outrage. You just do not do things like that in Singapore! Bizarrely, the culprit turns out to be a Swiss expat and he is now in deep doodoo.