KNOPPIX, WHOPPIX, AUDITOR, HELIX, and now BACKTRACK /~2 (based on Slackware) -- I use these goodies all the time! They are currently working on BackTrack3, and should be coming out soon. All these Linux flavors come loaded with Security & Non-Security utilities; I usually don't get the feel on raw distros, and don't use them unless there is a requirement -- such as in the production environment.

For those who aren't familiar with these live bootables; they have the ability to run on your machines with/without installing the OS on your local hard drive. They can also run on a vmware and similar virutal environments!  

cheers,

~@~