Helloooo,
I have just (this morning) put K9 on my laptop. It's free software which is a real bonus and I've spent a short time trying to break it just to see how good it is...
So far it seems to be un-bypassable (made up word

. The best feature so far is that it can be set to block all internet acccess if a set number of sites are blocked within a set time period. I have set it to block all web access for 30 minutes if I get 5 blocks within 5 minutes... hopefully this will give me time to cool down.
It also has different degrees of blocking, from full lockdown to a simple list of undesirable sites... I've put myself on full on lockdown!
Also since I have to know the password I made it something which to me basically says "don't be a loser you know that you don't want to do this". I hope that will make snap out of my p hunt if I ever resort to removing k9.
I'll keep you posted on how I get on with it.