Not really a hack, but rather a workaround for layout problems with IE.
Conditional

List all plugins installed in FF

Get computed Height of an HTML Element

Flexible sorting algorithm based on Quicksort with extra functionality, such as:
- Direction (ie: ascending or descending)
- Sort-by-path (eg: item.name, item.name.firstName or item[5])
- Sorting function (returns true if two items are already sorted)
- Type checking
- All constants and support functions are members of the Sort() function
- Testsuite with hooks for cscript and in-browser javascript, so you can tweak and optimize, and make sure it still works
- Environment agnostic (can use with, say, SpiderMonkey or .Net's jsc)

Here's a library to manage CSS class names on DOM elements.

Simple chatting script to be placed on a corner of a website
Also a good example how to use ajax.

Set a word or phrase in an input field, clear it onfocus

It works with Array types. The example is a simple list of numbers, but the array could contain anything; lists of strings, functions, DOM nodes, whatever. Unfortunately, a lot of things that seem like arrays in the DOM aren't really, so you can't shuffle the images on a page with just document.images.shuffle() all by itself.

Attribute Selectors

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