Perfect! Rated 5 out of 5 stars

I love it! I must have reduced the time I waste on computers by about 80 or 90 percent! (Although instead, I waste time following the link on the "page blocked by Leechblock" page to sign up and post a review lol)

This is why we're all on Firefox, the amount of fine-grained control some of these addons offer is just mind-boggling. This beast allows for various degrees of blocking lists of websites (such as news sites or forums you may spend all night reading), offering a full block or blocking for a certain amout of time per hour/day/whatever. You can even set passwords to stop yourself unblocking websites, hide the places you'd reach the options from and so on. It seems that you could even block a bunch of websites and then literally prevent yourself from ever being able to reach them again!
Fantastic job and *chapeau bas* from France (:

This review is for a previous version of the add-on (