One thing that's always been a source of a tension for me is how to handle navigating around a "web of documents". There are limits to what you can do with "in

One thing that's always been a source of a tension for me is how to handle navigating around a "web of documents". There are limits to what you can do with "in-band" links in the text before they get to be contrived, awkward, and non-discoverable. Users seem to have a revealed preference for on-page links to barely-related URLs and want those links to have some spatial consistency over time. So that means adding some "fluff" (nowadays presumably nested in a <navigation> tag) to every document. One past experiment with out-of-band navigation was framesets, but they had some significant issues (not least of which is that the URL pointed to a container rather than the contained document). Are there some other interesting experiments with out-of-band navigation? Or is adding some semantic tags to HTML as good as it gets?