regex101 : Free PCRE-based regular expression debugger with real time explanation, error detection and highlighting.
I Love Typography : I Love Typography, devoted to fonts, typefaces and all things typographical.
Use The Index, Luke! : A tutorial covering SQL indexing and SQL tuning for developers: avoiding unnecessary details about database internals.
SQL indexing is the most effect...
OWASP : The Open Web Application Security Project (OWASP) is a worldwide not-for-profit charitable organization focused on improving the security of software.
FireLogger : A sexy server logger console in Firebug