Two things I forgot to add: (1) I said I'm 'done' with most of the sections; that's not quite true. As a proud new owner of a physical copy of the book, I will be going through and finding all the spots where it says "see yyy on page 219" and adding hyperlinks to the appropriate section/table. (2) If you work on the Wiki to make changes, it would be great (since the chapters are so long) if you could add in headers with an ID for the section you're referring to. I've modified some of the Wiki pages already, but for example: If you have a comment about the aliasing section under "The Ruby Language", put in the Wiki page http://www.rubygarden.org/ruby?ProgrammingRubyTwo/TheRubyLanguage code like: <h3 id="aliasing">Aliasing</h3> ....my comment here... Not only will this help make clear what you're talking about, but the JS that synchronizes the sections passes the hash for the section to the Wiki when you click on that section in the TOC: http://www.rubygarden.org/ruby?ProgrammingRubyTwo/TheRubyLanguage#aliasing which will cause clicks on subsections in the TOC to synchronize the bottom frame to the appropriate section, if one exists. (Look at the url in the TOC to see what the id should be.) -- (-, /\ \/ / /\/