Hey, thanks for the suggestion. The specific advantage of Leechblock though is that once you switch it on, you can't go in and change the settings during the blocked time period, you just have to wait it out (unless you reinstall firefox, so i had to block out that website too, plus google...)
@Danashcoft - yeah it's to stop procrastinating, in the sense that you might say 'oh i'm only going to check facebook for a minute' but then before you know it 20mins have passed. You can set it so that it only allows you a certain amount of time on a site before it locks you out.
well i guess i'm just gonna uninstall IE cos no-one else I asked knew of an equivalent either.