This extension will unstar all of the starred items currently loaded in your browser.
The Google Reader™ app does not provide a way for you to unstar items in bulk, so you must resort to clicking every star one at a time. This extension allows you to unstar all starred items with one click!
How to use this extension:
1) Login to Google Reader™
2) Click on "Starred Items" in the left rail
3) Scroll all the way down to the bottom of the page and keep scrolling until all items have been loaded into the page.
4) Click the star icon in the upper right hand corner of Chrome™
This extension will unstar all of the starred items currently loaded in the browser. You may continue to see starred items if all of your starred items haven't been loaded. Just keep clicking the star icon until they are all unstarred.
Hope it saves you some time!
Tested on Windows 7/8. There is an issue with OS X that I'm investigating.