Logging off users

What is the best way to logoff users from my Unix system? I have done a search and found that you can do a w or who - find who is on, and ps-ef | grep <user> and kill their processes. But what if you have a bunch of users and you need them off the system quickly? Killing individual processes would take too long.

Much thanks.

outta.

ps -ef|grep <user>|grep -v grep|awk '{print $2}'|xargs kill -9

This will kill processes by this user, but if you want to kick him out - get this one