A Web Standards Primer from maccaws.org
Developing With Web Standards an excellent basic explanation of what web standards are and why they are good things that can help you design better web pages, faster and easier.
Dive Into Accessibility 30 days to a more accessible web site
Full Options - Cynthia Says Portal Tester
Full Options - Cynthia Says Portal Tester
and here's Bobby but I like the Cynthia Reports better, easier to read and figure out what to fix.
Bobby WorldWide to test web pages and help expose and repair barriers to accessibility and encourage compliance with existing accessibility guidelines, such as Section 508 and the W3C's WCAG.
Serving XHTML 1.0 This article very briefly describes some, often surprising, aspects of how servers send XHTML to the user agent (eg. a browser), and how common user agents handle the markup they receive. [website]
Valid DTDs (Doctypes) from the W3C
Validation Bookmarklets from gazingus.org
W3C CSS2
W3C CSS2: Generated content, automatic numbering, and lists Before and After pseudo-elements
W3C CSS3: Border
Web Standards Awards I stuck this in bloglines thinking it would highlight really nifty sites for inspiration on my own web designs but some of the sites are downright boring. The design at the awards site is nice but wayyyyy too narrow, haven't they ever heard of liquid design? Why make it leave half the page blank in a 1024x768 resolution? It's just silly.
The Web Standards Project
WaSP Buzz, blog for the WaSP, mostly uninteresting stuff