The Open Web Tools Directory lists the best available tools for Design, Code, Test, Debug, Deploy and Docs in a very cool HTML 5 display using the canvas element.
HTML 5: nav ambiguity resolved at zeldman.com is interesting because The Zeldman has the same problem I have with the HTML 5 specs, and also because the discussion that follows is fascinating. Don’t just read the article—read the comments, too.
CSS 3 Cheat Sheet (PDF) is another freebie from Smashing Magazine that is just begging to be used as a class handout. Match that up with the HTML 5 Cheat Sheet from SM that I mentioned a few days ago.