One of the more interesting modes of transport in Hong Kong is tram.
Known as Ding Ding (叮叮) by Hongkongese for the sound they make, trams run only in North Hong Kong Island. Ding Ding is slower than bus, and must stop for traffic light. In a city with highly efficient MTR (Mass Transit Rail) system, it is hard to imagine that Ding Ding survives into 21st century.
A trip on Ding Ding costs HK$2.30 for adults, or HK$1.20 for children under 12, regardless of distance. Ding Ding fare is really, really cheap. But my complaint is that the air at tram stations is choking...