I have some friends who have struggled with internet porn, and we have a group in church that simply mail each other the log files once a month. We have a little widget that 1) tracks the installs of all new programs (a guy who thinks "just this time" can install another browswer and then delete it to "remove the evidence" 2)sends out a list of the files in IE or Firefox or Opera. It is good for accountability.
I know about teens and chat rooms, but in my opinion, adult men and porn is a far worse problem. All that assumes men are professing Christians. I doubt non-professors would see much problem with it.
Don't even TELL your kids about History. And if it IS deleted, you can go to temp. internet files. I've been known to check!