Bookmarks
Here are some external resources I find nifty.
Mozilla Developer Network
Great documentation for html/js/css
Regex 101
An incredibly useful regular expression tool
SQL Map
SQL penetration testing
CSS Gradient Generator
For when you need a css gradient
Piskel
Incredible tool for creating sprites
Anki
Flashcard studying tool
SVG OMG
Optimize svg's
Virus Total
Protect yourself from sketchy stuff
Cryptii
A whole bunch of neat text operations