As featured in the book’s Security chapter, here are some useful online tools for security-related testing and information-gathering.

• .htaccess Password Generator
• List of User-Agents (Spiders, Robots, Crawlers, Browsers)
• Perishable Press 6G Firewall
• NSLOOKUP: look up IP addresses in the DNS
• MX Lookup
• Redirect Check
• Hixie’s UTF-8 Decoder
• HTTP Requests like a Pro
• HTTP Request Maker
• Analyze User Agents
• PHP Error Reporting Calculator
• IP/Domain Blacklist Check
• AskApache HTTP Headers Tool
• Geo IP Tool
• Unix Timestamp Converter
• Live Regex Testing for PHP
• HTTP Headers Check
• Packet Storm – WP Vulnerability Lookup
• Exploit Database – WP Vulnerability Lookup

Many more recommended links available in the book. If you know of any awesome tools that should be included, let me know and I’ll add them to the list.