"The Eichlerholic" here.
For those of you with Obscure Glass in your homes, a really cool holiday idea is to hang the holiday lights BEHIND the glass, as seen from the street!
Please see below for a link to a video of how this looks- I lovingly swept the camera super close to the glass- the effect is just as great from a distance. It looks doubly cool because the lights seem to float in mid air, as the glass hides the wires holding everything up.
When I do it, I don't even bother with a tree... I just hang the lights at all sorts of distances. Your atrium BECOMES your tree. Or a kind of psychedelic holiday fishbowl.