Huge collection of flat icon fonts for use in web development.
#css
Emmet Documentation
Child of ZenCoding, Emmet gives you some really powerful snippet-completion powers for writings lots of HTML quickly.
Skeleton WordPress Theme
Simple, responsive theme for WordPress. Also has a sibling project that just provides the HTML/CSS boilerplate (Skeleton) for any web site.
LiveCSS
Monitor a page and poll the CSS files associated to reload them if they change.
ProCSSor
Really nice CSS “prettifier” that handles all sorts of re-formatting stuff to make your CSS more readable.
Mobile-friendly
Opera’s guide to mobile device optimization
Orientation Example
Simple example of Orientation CSS for on iPad/iPhone.
Uniform
“Sexy forms with jQuery”
Styling the VIsual Editor via Themes
Styling the VIsual Editor via Themes
Quick tutorial from Andrew on how a theme can add its own custom CSS into the visual editor to make it more WYSIWYG. Also touches on adding custom classes to the Styles menu.
jQuery Masonry
Neat plugin that allows you to position things on a “vertical” grid rather than a “horizontal” one, so that all your blocks take up less vertical space and mesh up better.