Address bar grammar kinda sucks. It doesn't even throw us the bone of intuitive legibility. Let alone to the level of predictability. It just goes for strict path data. www.example.com/go_here/then_here/. It doesn't allow you to shortcut GUI navigation with text entry if you know what you're doing.
One recent Carsonified post was particularly inspiring: Conversational and short URLs on Rails
It was written by Jason Lynes, from www.hulabalub.com. Look at what he does. He goes for more natural language links in the path by adding clear facet names and the inclusion of prepositions:
The introduction of prepositions is awesome. There is one new thing for folks to learn, "_" is a space for spaced elements acting as one facet, No big deal.
Direct address address bar manipulation could be nice because it "upgrades" gracefully. If you know what you're doing, you do it and it's fast. You do a "natural language" keystroke search in the address bar. If you don't, you fall back on the website's navigation.
I'm curious about taking it a little further. Usually, headings are followed by attribution info. So what about if we tried to emulate this by enlisting the help of subdomains, instead of paths? Let's forget about backend inefficiency for the moment. What if your homepage is:
home.example.com? Your "about" page is named
about.example.com? And on top of that,
about_page.example.com too (so if someone's trying to guess it we'll try and predict mistakes)? BTW, we'll also have normal GUI navigation as the catch condition.
Can the subdomain act more like a natural language search field? Could you put
map.example.com to directly display the map element, or phone number?