Kills all of the user's processes - Slay

Slay is a simple yet very handy shell script that kills all of the processes belonging to a specific user and displays an (optional) "Your current session has been terminated." to the user being booted.

slay finds and kills all the user's processes at once, saving you the trouble of hunting them down and killing them yourself. slay has four modes: nice, normal, mean, and butthead. Mean mode kills any nonprivileged user who attempts to slay another user. Set your desired mode in slay shell script.

Slay Installation:
Open terminal from Applications > Accessories > Terminal, and type following command to install

sudo apt-get install slay

Using Slay:
Open up the terminal and type following command to kill the entire session of user 'test'

slay test

Another way to kill all the process belong to user 'test' is by using command: killall -u test