Rated 3 out of 5 stars
Useful for removing cookies after browsing.
The history cleaning function would also be very useful, if it worked - but it doesn't. Do not use this addon to clear your history! You should use another addon like "Stealther" or "Distrust" instead, if you want to make sure all history entries are removed.
The developer warns that "In some rare cases, the browser history may not be cleared totally." However, the cases are not rare at all! Just click on any .jpg image, or a page anchor link, a link to a php download script, or many other kinds of common everyday links, and you will see they are not removed from the history, when using the "remove all pages viewed from the browser's history" option. Those URLs will remain in your history, and will show up when typing in the address bar, for example.
The developer has acknowledged the bug, and has been very helpful in working to try to fix it, but says he is unable to. See https://www.mozdev.org/bugs/show_bug.cgi?id=22094 for more info. I have asked him to remove the function from the addon, because some people are still trying to use it, and may not see the warning - see the review from TrAsHeR51 for example.
So, three stars for the cookie-cleaning function, but just "close'n forget" about the history cleaning, unfortunately it's broken and seems that it won't be fixed.