Watcher is a Parental Control utility that limits the time your kids can use Safari, Instant Messaging, or even games on a daily basis.
At the same time, It allows you to setup a curfew for week days and week ends, so that your kids won't use the computer too early or too late. More than that, this program provides a detailed statistics of how long your son or daughter has used the computer.
In addition, the present version allows you to configure Watcher on a firewall-protected computer.