iTunes Statistics

Must be someone out there as much of a nerd as I am and like statistics from your music library?

There are apps both for the iMac / iBook and your mobile devices but the once i have found have some of the functions I like to have and another one has some other of them. So which program do you use for your statistics and why?

on iMac / iBook? on your iPhone? on your iPad?

Björn