Lalim Parallel Port Control can control hardware through the parallel port (printer port) and can also control a remote PC parallel port through a network.
If you are capable working with DC electronics, Lalim Parallel Port Control allows you to build remote-controlled, or timed, devices for your home or office – turning on or off the air conditioner, adjusting lighting, opening & closing windows, monitoring burglar alarms, and more.
To get the full effect of this it is helpful to have a small amount of electronics knowledge. You could do this simply by sticking the positive side of a LED into pins 2-9 on your parallel port and the negative side of the LED into pins 18-25 if you don’t have much electronics knowledge. However, below is the schematic for a simple array of LED. You could build this very easily if you know how to solder.