Greeting Sandbloggers and Sandboxers! Below are a few pages that I believe are useful for web development.
The first is a tip sheet on how to leverage the different php hooks, functions, and tags, in WordPress.
The page is centered around providing a centralized resource on what can be done in WordPress, such as creating your own post types and customizing your pages. There is a jump list to the right which organizes all of the content there:
The next is a list of uncommon CSS selectors which can be used to grab various elements on a webpage, such as all the paragraphs or only the first link: