Recovers hashed passwords

Wireless network password cracker for 802.11a/b/g WEP and WPA

Open-source environment for exploitation code development, testing, and execution. Has extensible integration of payloads, encoders, no-op generators, and exploits. It also downloads with hundreds of ready-made exploits.

Debugger with extended functionality and intuitive GUI.

Network intrusion detector, very lightweight.

Security Auditor's Research Assistant, multiplatform vulnerability assessment. Latest version released June 2009. Development has ceased.

Microsoft Baseline Security Analyzer Microsoft, detects vulnerabilities according to Microsoft's security recommendations and suggest possible solutions. Works with Windows Update Agent and Microsoft Update, MBSA collaborates with Microsoft management products including Microsoft Update (MU), Windows Server Update Services (WSUS), Systems Management Server (SMS) and Microsoft Operations Manager (MOM).

An extensive glossary.

Not as comprehensive as SANS, but has a special "Relevance" section on each term.

Server vulnerability scanner. Test for dangerous files/CGI versions on over 625 servers, and version specific problems on over 230 servers. Includes automatic updates.

Java based web proxy. Assesses web application vulnerability. Supports editing/viewing HTTP/HTTPS messages on-the-fly to change items such as cookies and form fields. Does web traffic recording and web spiders. Scans for web application attacks like SQL injection and cross-site scripting.

Nmap is a general purpose scanner and network administrator. It has abundant functionality.