if you want your bookmarklet to work in all browsers, it has to adhere to length limits: * IE 5 - 2084 bytes * IE 6 - 508 bytes * IE 6 SP 2 - 488 bytes * IE 7 - 2084 bytes * Firefox + Safari - > 2000 bytes IE6 has the smallest length, and that includes the javascript: pseudo protocol.

when you're on a page in which you want to play around with jQuery in the console, just click the bookmarklet.

The YUI Library is a set of utilities and controls, written in JavaScript, for building richly interactive web applications using techniques such as DOM scripting, DHTML and AJAX. YUI is available under a BSD license and is free for all uses. The YUI project includes the YUI Library and two build-time tools: YUI Compressor (minification) and YUI Doc (documentation engine for JavaScript code).

JSLint takes a JavaScript source and scans it. If it finds a problem, it returns a message describing the problem and an approximate location within the source. The problem is not necessarily a syntax error, although it often is. JSLint looks at some style conventions as well as structural problems. It does not prove that your program is correct. It just provides another set of eyes to help spot problems.

good introduction to js libraries

This is the home of the RDFa Javascript implementation, including the RDFa bookmarklets.

This JavaScript utility allows you to interactively browse the Document Object Model representation of a page. Its designed to help developers in finding the various objects, properties and values associated with elements and other objects in an web page.

This table summarizes the meaning of various strings in different regexp syntaxes. It is intended as a quick reference, rather than a tutorial or specification. Please report any errors.

Features: You can enter statements and expressions at the same prompt. The result of each non-void statement or expression is shown. User-defined variables. b = document.body User-defined functions. function f() { return 5; } JavaScript error messages are shown in red. Previous statements and expressions are available through Up and Down arrow keys. Tab completion. Multiline input (Shift+Enter to insert a line break). If the shell is opened using a bookmarklet, JavaScript typed into the shell runs in the context of the original window. Works well in Firefox, mostly works in Opera 8 and in IE 6 for Windows. Suggested uses: Test short bits of JavaScript, bookmarklets, or user scripts. (For longer bits of JavaScript, try the JavaScript development enviornment too.) Explore DOM objects such as document.body using props (Alt+P) to figure out what is possible. Explore the DOM of a specific page using the bookmarklet version of the shell. Modify the DOM of a specific page using the bookmarklet version of the shell. Use the shell like you would use the home screen of a calculator such as a TI-83. Alt+M gives you easy access to math functions such as sin and pow.

As the first online Regular Expression tester to offer realtime highlighting and offering more languages than any other online tester, ReJAx continues to be the coolest and easiest to use Regular Expression tester on the web. Supported languages:
    * JavaScript
    * PHP 5 PCRE
    * PHP 5 POSIX
    * Ruby - BETA!!
    * PERL 5
    * UNIX Shell Pattern
It is not necessary to enter the beginning and ending slashes in the pattern field. Not all modifiers will be compatible with every language. Backreferences (when available) are usually in the form of \n where n is the reference number