It has to be the Google PageRank Status Checker, which works just as it should.
It sits in the corner of your screen and doesn’t draw attention to itself. When you want to know the PageRank of the page you’re on, according to Google, just take a quick glance over.
It’s great when you have a large site to cover and you want to be continually informed of how it’s doing page-rank wise.
It’s also very useful when you’re surfing, and are interested in how ‘well’ a website is doing.
A bit better than the overlarge Google toolbar, methinks.
Yeah, the pagerank bit on that tool bar is just about the only think I used it for, so this extention makes it a bit useless.
What’s really nice about it of course is that you can disable and re-enable it easily so that unlike the normal toolbar you’re not constantly sending Google your browsing history.