As I was growing up, sunday mornings getting ready for church were always umm Interesting. You see we had 6 ppl in my family and usually only one bathroom. And we aren't the kind of family to walk in on each other.
I was reflecting back on this yesterday and how I, always really wanted to solve this problem. The best thing I had come up with to date involved parabolic mirrors, so it wasnt terribly practical.
I think I might have it licked though...
In a bathroom with this configuration, 3-4 ppl can operate simutaneously without any interference. At least, that is, as long as someone has evacuated before the person in the shower comes out. :P