From February 8th, 2012 to November 1st, 2012, 50% user give 5-star rating, 50% user give 4-star rating. for Your Title Here chrome extension.
Does what it says! Also works for bookmarks that are local files (assuming you check the little box on the chrome://extensions page).
It works nearly everywhere except GMail. As GMail loads, the extension works perfectly. Once GMail finishes loading and changes the title to show the number of unread messages, the extension's title is lost.