I dunno if anybody wants to take things in this direction, but lemme just spew forth something floating around in my brain. Mozilla / Netscape 6 and later have a neat sidebar functionality; basically, it's a very narrow HTML page that you can use to quickly access all sorts of content. It's great for Google (keeps the result of your searches in the sidebar so you can visit many results without using the back button etc.). But I'm not plugging Moz here so much as thinking it might be cool if PM (or the Everything engine) could generate a sidebar page with, say, the 5 most recently added nodes and the search box. It doesn't need to be fancy, and it wouldn't detract from the functionality of the site for other user agents. The URL could point to a page that's statically generated every so often so it wouldn't generate extra server load.
Building such a creature is easy: just spew out the HTML from a given URL, making sure it looks OK at around 150 px wide, and make sure all the links have a target attribute of "_content".
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I mistrust all systematizers and avoid them. The will to a system shows a lack of integrity -- F. Nietzsche