Insecure.Org has released in 2006 a survey password crackers tools and 3,243 people responded. Respondents were allowed to list open source or commercial tools on any platform. According to the survey, the most efficient tools for password cracking were:

1. Cain and Abel : The top password recovery tool for Windows

   Cain & Abel is a password recovery tool for Microsoft Operating Systems. It allows easy recovery of various kind of passwords by sniffing the network, cracking encrypted passwords using Dictionary, Brute-Force and Cryptanalysis attacks, recording VoIP conversations, decoding scrambled passwords, recovering wireless network keys, revealing password boxes, uncovering cached passwords and analyzing routing protocols. The program does not exploit any software vulnerabilities or bugs that could not be fixed with little effort.
   

2. John the Ripper : A powerful, flexible, and fast multi-platform password hash cracker

   John the Ripper is a fast password cracker, currently available for many flavors of Unix (11 are officially supported, not counting different architectures), Windows, DOS, BeOS, and OpenVMS.
   

3. THC Hydra : A Fast network authentication cracker which support many different services

   A very fast network logon cracker which support many different services

4. Aircrack : The fastest available WEP/WPA cracking tool

   Aircrack-ng is an 802.11 WEP and WPA-PSK keys cracking program that can recover keys once enough data packets have been captured.
   

5. L0phtcrack : Windows password auditing and recovery application

   L0phtCrack is a password auditing and recovery application (now called LC5), originally produced by Mudge from L0pht Heavy Industries.
   

6. Airsnort : 802.11 WEP Encryption Cracking Tool (Not supported anymore)
7. SolarWinds : A plethora of network discovery/monitoring/attack tools

   SolarWinds has created and sells dozens of special-purpose tools targeted at systems administrators. Security-related tools include many network discovery scanners, an SNMP brute-force cracker, router password decryption, a TCP connection reset program, one of the fastest and easiest router config download/upload applications available and more.
   

8. Pwdump : A window password recovery tool

   Windows 2000/XP/2003/Vista/2008 NTLM and LanMan Password Grabber
   

9. RainbowCrack : An Innovative Password Hash Cracker

   In short, the RainbowCrack tool is a hash cracker. A traditional brute force cracker try all possible plaintexts one by one in cracking time.
   

10. Brutus : A network brute-force authentication cracker

    Brutus is one of the fastest, most flexible remote password crackers you can get your hands on - it’s also free. It is available for Windows 9x, NT and 2000, there is no UN*X version available although it is a possibility at some point in the future.

Popularity: 98% [?]