Javascript

Here is a nice article addressing the pros and cons of jQuery .bind .delegate .live and .on. It also shows how in jQuery 1.7.1+ they all map to .on

http://www.elijahmanor.com/2012/02/differences-between-jquery-bind-vs-li...

Adding these comparisons do I don't have to go look them up each time

This is a handy little function that can be used for debugging in Drupal. SInce console.log can sometimes break some browsers without a console, this at least makes sure the console.log is only run when you are logged into the site. It also has a nice feature of including the name of the function that called it.

One difficult aspect of cookies is determining if they are blocked or not when loading a single page. (for example trying to determine whether someone is the first time visitor to a page or repeat visitor with cookies disabled.)

Here is a nice php technique for testing whether cookies are enabled or disabled

A quick non-library way to safely look for a GET value and do something with it.

When debugging Ajax call returned Jason data this is very useful makes the data easier to read.

http://www.jsoneditoronline.org/

Beautifying javascript  

http://jsbeautifier.org/