L0phtCrack

L0phtCrack was developed by L0pht Heavy Industries to reveal the security flaws in Windows authentication system. Now it lists out itself as one of the best Windows based password hacking tools. Its popularity is so high that nearly every password dumping tool dumps password in L0phtCrack compatible format or has option to dump password for L0phtCrack. It attempts to crack Windows password from hashes which can be obtained from standalone computers, networked devices or active directories. It supports various methods to attack for getting valid password including dictionary based attack, rainbow tables, hybrid attacks and even brute force. If used with proper hardware there's no way any password can withstand its might. The best part it is that it now supports cracking Linux and UNIX password too. You can download and use it for 15 days as trial.