Check out the Firefox Tree Style Tab plug-in [1], is this what you had in mind?
[1] https://addons.mozilla.org/en-US/firefox/addon/tree-style-ta...
Chrome might be faster than FF and a Ferrari might be faster than a pickup truck.
But:
FF and the pickup truck is more useful for work IMO
and the Ferrari and Chrome comes with a price I'm not comfortable with.
You might have better luck with trying to implement it as an extension to Firefox although the extension API is (at least for now) going to be a shadow of its former self AFAIK.
My tab tree is the closest thing I've come to an effort-less mind-map that works for me. (Effortless as in ctrl-click to open a new sub-tree so I can always see what is related to what and how I found something really hard-to-find-but useful.)
Even though my current setup works well I'm quite sure I or someone else will be able to create something event better in the future.
http://lifehacker.com/203915/download-of-the-day-pathway-mac
to "solve" the tab problem, you need to combine tabs, history, bookmarks, back/forward buttons, pinboard/tags/pagecache into groups that are instantly rearrangable by their proximity to each other: spatially, by topic, or temporally. i should be able to, in one command, show only tabs that are hacker news or originated from hacker news, but maybe something i googled while on one of those pages deserves to be related. now the machine should be making inferences on what goes where, and i give it feedback when it is wrong.
tabs should be more like a wiki document, where as i accumulate more about, say, stagecoaches, or good reads from redef, those metadata relationships to topics and origins are preserved. i should be able to go back and show only bookmarks from only hackernews/redef/longreads combined, and only the ones about stagecoaches.
i know mozilla has shown a demo of something like this, but its a long way from being more useful than tabs, because it neglects the content of the page itself.