To me, the most enjoyable transport in Bangkok must be Chao Phraya Express Boat Service. Chao Phraya River is the bloodline of Bangkok. All sort of activities happens along the waterway, creating a vibrant livelihood unlike the enclosed views you get from the road. You can capture people and their relationship with water as well as amazing abstract urban landscape while feeling the fresh air.
Go with the Flow music slideshow starts from the trip from Central (Sathorn) Pier, which is conjunct with the end of skytrain line at Taksin Station, to Wang Lang (SiriRaj) Pier.