Internet safety for children

Is internet safety a major concern for your children? Here's a website that I've come accross: checkmypc. It can help protect children online by checking the PC for porn, misguided actions or affairs, or other stuff. It checks from all the different sources like surfing history, stored files and documents, or installed programs for questionalbe content. It can also be used to check computers of employees who are supposed to be working but are actually doing other stuff on the job. Of course the program should be used with discretion, as overusing it without reason is an invation to privacy. It shouldn't probably be used on older kids who can think for themselves.