Introducing SkyBus. RM9 one way from KL Sentral to the new Low Cost Terminal in Sepang and vice versa. Comparatively the ERL charges RM38 for a one way ticket, while a cab could cost anywhere between RM50 to RM70. SkyBus claims to be able to get you there in 1 hour and 15 minutes.
Melbourne has its own SkyBus which departs every 15 minutes from the city to the airport terminal about 25 kilometres away and it looks something like this.
You've got to wonder if the Malaysian Bus will look anything like.