There are some out there who have the ability to use the highest DPI setting on their mouse. I am most assuredly not one of those people as my eyes have a hard time keeping up if it gets too high up there. While I thought 2000 DPI was pretty impressive, Roccat laughs at me and puts out a very cool model which has an insane 4000 DPI.
The Savu Hybrid Gaming Mouse is crazy fast and wonderfully comfortable. It utilizes something called Easy-Shift[+] technology, giving you the ability to set two configurations for each button on the mouse. You will program one button to shift the other buttons to the second configuration, and take you from say, a seven button mouse to a twelve. There are fancy colored lights that you can customize, with a whole 16.8 million different colors to choose from. While this mouse may cost about $60, it is well worth its weight in gold for those who like to live in the fast lane. (Or just like to play FPS games)