My friend Scott has a great posting about manipulation techniques. Some of the stuff I heard before in a documentary about Walmart marketing techniques, but the “lecture” by Prof. Barry Schwartz is very impressive.
[flash]http://www.youtube.com/watch?v=Iy8R5TZNV1A[/flash]
After watching the video it seems that sometimes simple psychology can work as good or even better than some high-end web analytics solution 
