Eyes Relax is a little free Windows utility that reminds you taking breaks when working with computers. This software allows you to customize the duration of your work time and length of breaks.
During the break you may exercise your eyes, look away or look at distant objects either in your office or outside, take a stroll outside your office.
A "Parent mode" feature available in the new versions can be used to protect your children, forcing them to take breaks. In "Parent Mode" Eyes Relax cannot be disabled and the computer is password-protected when there is a break time. This is very useful since children often forget about the real world and play video games much too long.