W3
Web Style Sheets. CSS tips & tricks
http://www.w3.org/Style/Examples/007/

Alista Part
CSS Design: taming (X)HTML lists, creating great-looking navigational menus and other visual effects.
http://www.alistapart.com/stories/taminglists/

Poolie Studios
Add Icons to your Textlinks with CSS. Links are fun, but sometimes we don't know where they take us. With this little CSS technique a user can identify a link by its icon.
http://pooliestudios.com/projects/iconize/

Web Designer Wall
CSS Gradient Text Effect. Do you want to create fancy headings without rendering each heading with Photoshop? Here is a simple CSS trick to show you how to create gradient text effect with a PNG image (pure CSS, no Javascript or Flash).
http://www.webdesignerwall.com/tutorials/css-gradient-text-effect/

Exploding Boy
Free CSS Navigation Menu Designs at exploding-boy.com. Exploding-boy.com was designed and created by Christopher Ware in 2005. The site covers a wide array of topics but mostly focuses on design and life, with the occasional sprinkling of profanity-filled ranting for good measure. The site is powered by Wordpress, using XHTML for structure and CSS for presentation. This provides a great deal of increased accessibility and compatibility, as compared to traditional HTML table-based designs. The site is hosted by the wonderful people at DreamHost.
http://exploding-boy.com/images/cssmenus/menus.html#

Mezzoblue
Mezzoblue is a weblog. It was once a portfolio site, then a portfolio/weblog, then a weblog/portfolio, but these days it’s pretty much entirely weblog. I host other content here and there, but you’re mainly here for the writing.
http://www.mezzoblue.com/tests/revised-image-replacement/

Web Reference
How to Add Fluid Borders to Your Boxes with CSS.
http://www.webreference.com/programming/css_borders/

html Goodies
HTML Goodies intended purpose is to help new and growing website developers learn their trade, and to provide them with tips, guides and reference sets for their use as they become more accomplished. To that end, we have arranged the site into sections that range from a completely non-technical introduction to the concepts involved in developing websites all the way through to keyword references. The following is an overview of these various sections.
http://www.htmlgoodies.com/beyond/css/article.php/3629021

SEO Consultants
In this section of the SEO Consultants Directory, you'll find onsite links to various information relative to Cascading Style Sheets and other CSS Tips and Tricks along with information pertinent to Website Design.
http://www.seoconsultants.com/css/tips/

Site Point
CSS can be complex, and as each new browser version is released, you may well find yourself struggling to keep up with the latest tips and hacks. But those tips and hacks will save your sanity! Here, I've put together the ten tips that I find most helpful, to save you the hassle of scrounging around the Web for solutions when time is tight.
http://www.sitepoint.com/article/top-ten-css-tricks/

CSS Tricks
Tips, Tricks, and Techniques on using Cascading Style Sheets (CSS)
http://css-tricks.com/

456 Berea Street
This site is a place for me to post articles, tutorials, and comments on subjects that are interesting and useful to me and hopefully to other web professionals. Most posts on this site are related to web standards, accessibility, or usability in one way or another, with the occasional post on other subjects.
http://www.456bereastreet.com/archive/200503/css_tips_and_tricks_part_1/

Peter Freitag
I never cease to be amazed at what problems can be solved with pure CSS. Here are 20 CSS techniques, tips and tricks that you may find handy.
http://www.petefreitag.com/item/475.cfm

Evolt
Ten CSS tricks you may not know
http://www.evolt.org/article/Ten_CSS_tricks_you_may_not_know/17/60369/