Detecting root kits?

[Dan Coutu]

Last week I uncovered a RedHat box that had been rooted (fortunately it 
had only recently been installed and nothing important was on it.) 
Rather than me having to go through a hands-on intensive process of 
analyzing every other Linux system on the LAN are there tools that I can 
use to determine whether or not this SOB got into other systems?

Any pointers to where I can learn more about the different types of 
rootkits and how to counter or detect them are also welcome.

Thanks!
-- 

Dan Coutu
Managing Director
Snowy Owl Internet Consulting, LLC
http://www.snowy-owl.com/