Here are some usefull links that I have been handing out a lot lately. The solution is to update this page often, something I will do.

Ajaxian's links
A whole bunch of ajaxian links, from javascript to css and json.
Efficient javascript
A nice article about how to write efficient javascript
CSS media types
A very nice article about css media types, by fellow 'happy clog' Kilian Valkhof
favicon creator
A simple way to create a favicon
Browser stats q3 2007
Just to know whtat you are up against...
Faux console
With this, you can use console.log() safely and even MSIE will show you the output in a small dynamically generated DIV on the page.
Fix Your Site With the Right DOCTYPE!
An old but still usefull zeldman article on AlistApart. Here the different doctypes are explained. Also the difference between quirks en standards mode...
An essay that explains the Ajax principle.
Lists revisited
How to create a menu from UL's that is accesible to keyboard users...
Usefull tricks for testing and many more purposes...
How to make IE behave itself, using very advanced javascript.
Cross browser 'modal' dialog...
css1 in ie6
IE reference..
Javascript debugging in firefox, by Joe Hewitt
Firebug for other browsers
Firefox for other browsers, ie, safari and such. Not as great as the real one, but still better than nothing.
Webdeveloper Toolbar
Web developer toolbar for firefox by Chris Pedrick. A must for any serious webdeveloper
IE developer toolbar
Web developer toolbar for IE
X-ray vision for html pages...
Validate html
Validate your html pages and live happily ever after...
Validate CSS
Validate your CSS code...
I didn't know how much I needed this, finally an ad free web..
Getting real
The online version for us (dutch) cheapskates who don't want to spend any money, but still like the read the 'getting real' book from 37 signals.
Css documentation
Css documentation online
After a long time I finally found a javascript library that suits me.
Visual jquery
Visual jquery documentation
A compilation of javascript links