The only thing i have used them for is to calculate the amount of time people are sitting on my site. I dont have the math in front of me but when i get home ill find it. I have tried to look over pages that people have spent more time on, to see if there is somethign graphical that keeps them there. For my one site it's a little tough cause the surfers could be looking over 1 perticular cam model they like more then the others. That post I put was not my words, just what I found on the webmonkey
when i find the math stuff I'll post it here for you. Don't know if it will help tho.