• FTP and remote login clients:
  • FireFTP FTP client for Firefox that runs in a browser tab. By Mime Cuvalo
  • sFTP Client for Chrome From www.sftpclient.co.uk (not free?)
  • FireSSH SSH Add-on client for Firefox that runs in a browser tab. By Mime Cuvalo
  • Secure Shell SSH App for Chrome. By Google.
• Web Developer Toolbar Extension for Firefox and for Chrome. By chrispederick.
• ColorZilla Advanced Eyedropper, Color Picker, Gradient Generator and other colorful goodies for Firefox and for Chrome. By Alex Sirota

Note: All of these validators can also be used directly from the Web Developer Toolbar for Firefox.

• Validators
  • W3C HTML Validation Service or Use the Nu Html Checker at https://validator.w3.org/nu/ directly instead.
  • W3C CSS Validator
  • W3C Link Checker
• Code Checks
  • Online interface for Dave Raggett's HTML Tidy by Jonathan Hedley - Clean up bad or obsolete code; lets you paste in code and upload a file as well as give a URL
  • Another online HTML Tidy
• Accessibility Checks
  • Vischeck - Test images and web pages for color blind visibility.
  • WAVE 3.0 Accessibility Tool
  • Cynthia Says accessibility validator
• Browser Checks
  • Overall support for HTML5: HTML 5 TEST (http://html5test.com)
  • Support for specific HTML5, CSS3, or SVG elements: Can I use... (http://caniuse.com/)
  • Browser market share: StatCounter Global Stats(http://gs.statcounter.com/)

• Fonts and Typography
  • Typetester - Interactively compare fonts for the screen
  • CSSTXT Another tool for experimenting with text stylings.
  • Browser-safe fonts - Common fonts to all versions of Windows & Mac equivalents
• Color Palettes
  • Color Palette Generator - Enter the URL of an image to get a color palette that matches the image.
  • Infohound Color Schemer - Enter a color value to get a palette of compatible colors.
  • colordb Color Database - Another Color Palette generator.
• Miscellaneous
  • Character Entities in HTML & XHTML Comprehensive reference at the Web Standards Project
  • Wordle - Create word clouds from entered text. for the desired emotional effect.
  • Lorem Ipsum Lorem Ipsum filler text generator.

• The Web Standards Project
• HTML 5 Specification (W3C)
• XHTML 1.1 - Module-based XHTML (W3C)
• CSS (W3C)
• Web Content Accessibility Guidelines 1.0 (W3C)
• Web Content Accessibility Guidelines 12.0 Quick Reference (W3C, not final)
• Federal Rehabilitation Act Section 508 §1194.22 Web-based intranet and internet information and applications.

• A List Apart Online magazine on Web Design. Articles by top professionals.
• css Zen Garden/ - Showcasing the beauty and versatility of CSS.
• CSS Edge - Examples, articles, and more by Eric Meyer (CSS guru).
• useit.com Articles and papers by Jakob Nielsen (Usability Guru)
• W3 Schools - Tutorials and references. Not in-depth, but good for a quick intro.
• Web Design References Comprehensive lists of resources at University of Minnesota, Duluth.
• maxdesign.com.au The "articles" and "CSS" sections have some good info and links.

• Advanced Computing Systems Association: (USENIX)
• Association for Computing Machinery (ACM)
• Association of Information Technology Professionals (AITP)
• Computer Society of the IEEE