A small tree grows near my door and extends through an opening in the outside roof. I've always like little design variations like this. I always thought it would be cool to have real plants, soil and a small stream running inside. I know a family that once had a house with a water feature. Pretty cool. I remember when Lloyd Center in Portland had an open roof and many plants inside. I loved it that way - though the rain could make a mess sometimes. There is an outdoor mall in Teresina Brazil. It has some of the same appeal - though indoor malls are better there because it's so ridiculously hot! I'm sure this sort of stuff causes for many types of problems, however.