Metsploit is a very Powerful PenTesting Tool . Metasploit Framework, a tool for developing and executing exploit code against a remote target machine. The Metasploit Project is also well known for anti-forensic and evasion tools, some of which are built into the Metasploit Framework. Very useful tool for Information Gathering, Vulnerability Scanning, Exploit Development, Client side exploits,...
Official site: http://www.metasploit.com/
Official site: http://nmap.org/
Official site: www.openwall.com/john/
This tools is not free one ;(
Official Site: www.acunetix.com