Web

General information sites

A List Apart

Smashing Magazine

QuirksMode

Core web tech

HTML

JavaScript

CSS

PHP

Fonts

Design

Luke Wroblewski

Yahoo design pattern library

http://www.designingsocialinterfaces.com/

http://designinginterfaces.com/

http://ui-patterns.com/

http://quince.infragistics.com/#/Main

http://box.mepholio.com/

http://www.uxmatters.com/index.php

Interface design patterns browser

Example Sites

http://www.highcharts.com/

http://www.bumblebeelabs.com/

http://actionbarsherlock.com/

http://growl.info/about

http://finegoodsmarket.com/view/

http://pupunzi.com/

Blogs

Webification (library pointers, reviews, news and interviews)

Steve Souders performance blog

Designer David Shea's blog

Tutorials and Tools

Wide range of subjects, including Photoshop, coding, etc

Makers of XRAY, MRI, gradient design tools and more

jsFiddle interactive js/CSS/HTML test tool

Background sprite creation

Balsamiq mockup tool

Articles

Color theory: contrast vs. readability

Services

http://www.google.com/recaptcha

Marketing

http://blog.kissmetrics.com/