I think www.amazing1.com and some other stores sell some laser
light listening devices.I think the way they work (or suppose to work)
is the laser light picks up vibrations from sounds behind the windows
and converts the vibrations into sounds you can hear with head phones
connected to the laser light listening device.I have never tried out one
of those rigs though.Do a search for, Laser Light Listening Devices

I think I have a fancy kalideoscope around here somewhere that I bought
about thirty years ago.I used to play with those gadgets when I was a
kid.
cuhulin