Yea, you read that right. Three commands and you can run a pen-test on your website/webserver. So, how?
kelvin@home:~$ sudo apt-get install nikto
kelvin@home:~$ sudo nikto -update
kelvin@home:~$ nikto -h www.thoughtdeposit.net
kelvin@home:~$ sudo nikto -update
kelvin@home:~$ nikto -h www.thoughtdeposit.net
As you can see, Nikto is a web server scanner, apparently for over 3200 dangerous files/vulnerabilities. Additional features can be seen at the Nikto website, yet you will certainly want to add this old gem to your webserver toolbelt as soon as possible.