Here’s a select list of my favorite technical writing resources. I use these all the time:

Web Programming and Design

• HTML Entities, and URL encoder/decoder
• Web font statistics and Esperfonto font selection tool
• Browser Statistics and Browser Display Dimensions
• CSS Examples and online testing tool and CSS-Discuss wiki. Also, a listing of browser support for new web standards.
• Elements of Typographical Style applied to the web by Richard Rudder. Guided by Bringhurst’s principles.
• Embeddable Web Fonts Wiki and how to embed fonts. See also Fontsquirrel’s embeddable fonts which are free for commercial use and Kernest fonts (which seem to be web-embeddable; doublecheck). See also this thread and this guide to different kinds of embedding.
• Section 508 Compliance and W3 Web Accessibility Guidelines
• Tutorials: XSL, XML Schema, xpath

Tools

• Zamzar free file conversion wizard.
• Utilities: winmerge, Tortoise SVN, filezilla, putty
• Snagit (online demos & online help), a $49 screen capture utility with extra features.
• Open Source Publishing: scribus, gimp, inkscape
• Freeware utility index
• Screencasting programs: Camstudio (Windows only), Wink
• Notetab Light, main text editor I use (Windows only).
• Windows Live Writer, a desktop xml-rpc friendly blog editor.
• Oxygen XML Editor. Full-featured commercial xml/xslt editor (with forums). See also XML Mind (also commercial) which is targeted towards documentation.

References

• Subversion Book
• Typographic Design Patterns and Best Practices and 10 Useful Usability Findings and Guidelines.  By Smashing Magazine.
• Better Font Stacks by Nathan Ford. See also codestyle’s font stack articleand Micheal Tuck’s article on the same topic.
• Organizing Content is a 15 part series by Tom Johnson  about the challenges of information architecture and usability. Highly recommended.
• Oasis OpenDocument Ebook
• CSS Wiki and CSS Mailing list
• Technical Writing: Online TW Textbook and Managing Technical Writing online book
• Help-Authoring Matrix: Let’s you find the right documentation tool for the job. Note: software companies pay a fee to be listed here.
• Indoition has a good index of technical writing resources, including a review of Help Authoring Systems, Screencasting Tools and a Documentation Quality Checklist.
• Reference Cards: restructured text and an index of other cheat sheets.
• S5 Web presentation reference guide. Fascinating single-source solution for presentations.
• Klariti information re technical writing. They sell excellent-looking MS Word templates of assorted project/planning documents which technical writers usually have to submit to project managers.
• Agile Documentation, Scott Ambler’s summary of how documentation interacts with project management.

XML Flavors: Docbook and DITA

• Docbook Definitive Book, and Docbook XSL book
• Docbook-apps mailing list,
• Docbook HTML parameters reference (also the fo parameter reference).
• R.L. Hamilton’s article on DocBook vs. DITA
• DITA: 1.1 Specification, DITA XML Wiki, Ditaworld, DITA Users Mailing List, Dita for Publishers epub plugin,

Education & Technical Writing Weblogs/Portals

• I‘d Rather Be Writing is Tom Johnson’s cutting edge blog about documentation, blogging, wordpress and tech writing topics.
• UX MAtters is a academically-oriented usability blog
• elearningpost , an outstanding site with links to usability, information architecture and instructional design.
• Content Wrangler, a good news site on new technologies in documentation.
• Elearningcurve, a blog about instructional technology and technical writing
• I Came, I saw, I learned is Iconlogic’s blog with tutorials, reviews about technical writing products (Adobe, Camtasia, etc).
• User Advocacy, weblog by Houston technical writer Chris Borokowski
• Just Write Click is a  blog by  Austin technical writer Anne Gentle.
• I occasionally write posts about technical writing on my idiotprogrammer weblog.
• Creating Passionate Users by user advocate Kathy Sierra
• This is Broken (Good Experience) Weblog humorous weblog that illustrates usability and documentation problems by using real life examples.
• Oreilly XML Weblog, a series of articles written by O’Reilly authors.
• Jim Thoughtspot, XML Technology blog, with emphasis on DITA and technical writing.
• Boxes and Arrows, a leading site for information architecture and user interfaces. They have sections for Findability, Usability, and Learning from Others, plus a lot more. No RSS feeds for each section, but lots of articles added weekly.
• Open Office Training Weblog, full of tutorials and resources.
• TECHWR-L Forums, google group mirror of world’s largest mailing list for technical writers.
• Microsoft.public.word.docmanagement, a high traffic newsgroup for MS Word users.
• Daily Blog Tips &  Weblog Tools Collection allow you to stay current about WP weblog technology

Houston/Texas Resources

• STC-Houston Forum
  
• Techblog, Dwight Silverman’s excellent technology blog for the Houston Chronicle. (I briefly wrote some guest articles for this blog).
• Idiotprogrammer Weblog. My personal weblog which covers a wide range of topics (not just technology). The weblog has a section specifically devoted to technical writing and even a separate RSS feed for technical writing.

Epub & Ebooks  Resources

• Oxygen XML: Oxygen-user mailing list; Latest user manual; video demos
• Epub Specifications: OPS,  OPF
• Free & Budget Epub creation tools: Jutoh, Calibre (User Guide), Atlantis, (blog),  Writer2epub (with English forum),  (Export from Open Office),
• Epub Zen Garden
• Epub Resources (collected by Keith Fahlgren); Epubcheck tool (and online version)
• Blogs:  Threepress Epub blog, Epub books blog, Tools of Change and the irreverent ebook test
• MobileRead epub forum and Calibre ebook conversion software
• list of ipad’s ebook reader apps (June 2010)

Podcasts

• SXSW Podcast, lots of podcasts from SXSW conference, with many topics of interest to technical writers.
• IT Conversations, a leading portal for podcasts on new technologies (especially web technologies).

Book Production

• a free download to people making print books on Createspace (with generally useful information).
• Mobileread list of free and commercial ebook sellers.
• Stanza FAQ
• discussion about using wordpress for book publishing