This article has tips on how to avoid hacking on WordPress sites and also the steps to follow after a site is found to be hacked.
This ebook provides tips on speeding up WordPress sites.
This presentation provides tips on coding best practices for WordPress.
This WordCamp presentation outlines steps to secure a WordPress site.
This plugin enables the use of Google Authenticator two factor authentication for logging in to WordPress admin.
This article lists several HTML5 development tools.
This tool from Microsoft allows you to use a virtual machine (e.g. VirtualBox) and test sites for compatibility with IE6 to IE11 on various operating systems (all the way to Windows 8.1).
This site provides user interface design examples for a variety of situations e.g. online form, shopping cart, etc.
This presentation provides various points to keep in mind when designing a mobile website.
This site provides free responsive HTML5 templates that you can be customised.