Unread Google Reader is a simple Google Chrome add-on that adds a toolbar next to the URL bar which displays the number of items currently unread in the Google Reader feed which is logged in to.
Google also has an official extension similar to this one, but the Unread Google Reader add-on takes you directly to Google Reader in a new tab when you click on it, instead of showing the unread items.
Unread Google Reader is cross-platform and it works on Mac OS X, Windows and Linux.
Requirements:
· Google Chrome