The prayer ceremony by the ghats of the holy river Ganges, is an impressive event. At 6pm sharp, every evening, priests ('pujaris') all in white, line up in a row, and amidst fire and chanting and the sound of bells, they perform a choreographed ceremony. A pretty impressive sight.
See my `aarti' travelogue for more pictures...
I would suggest going to bed early and get up before sunrise in the morning! It is really worth it. The sun comes up on the other side of the river so if you take the boat along at sunrise you will have a great light shining on all the ghats and buildings packed on top of each other.