15 of 21Image
PageRank Status is a helpful little tool. I don't usually click the toolbar button, but the toolbar button itself changes, providing a page rank status indicator for pages I visit. Since I'm often chasing down interesting articles, that little indicator gives me, at a glance, a superficial indication of whether or not the page I'm currently reading is one that's relatively influential or just a voice in the wilderness.
How often used: I glance at it relatively constantly, as part of my normal surfing habits.
Live without it factor: I could live without it, but I'd prefer not too.