Choosing to install glass block windows in your shower or bathroom will reap the benefits.  For one you are allowing for natural light to enter the bathroom. With this natural light you can keep interior lights off during daytime showers reducing energy costs.  With that, glass block windows allow for natural light to enter your shower or bathroom while still giving your privacy while using the bathroom because outsiders can only see blurs while looking in.  Further, glass block windows allow for an added appearance in your bathroom giving the room a unique and different look.