...in case you don't want to install the Google Toolbar (like because it's broken or crashes). This is the JavaScript bit you'll need to add as the bookmark's location in browsers like Firefox or Chrome:

In Firefox, you can additionally add a bookmark keyword. I picked the word "pr", for instance; now when I visit a given site I can enter "pr" in the address bar, hit return, and a new window pops up showing the PageRank of the URL.

Included links: ChromeFans

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