How'd I Get Here?

How’d I Get Here is a new Firefox extension that, as the name suggests, helps you backtrack your path to the current page.

• Go “back” even after opening a link in a new tab and closing the original tab.
• Remember how you found a site you bookmarked yesterday.
• When you are sent a link you have already seen, astound the sender by responding with a statement more precise than “I saw that on some blog a few days ago.”

One problem: You have to be running a trunk build of Firefox. Definitely a nifty idea, though.