You laugh pharge, but in reality that's exactly what would happen and theres nothing wrong with it. You don't think that water you drink everyday has never had piss in it before do you =). But really as long as I don't know I don't care, but I would be hard pressed if I saw somebody piss on the building to go to the water fountain lol.
As far as the building I think it looks freaking awesome. They should diffently build it.
I predict that someday massive buildings will be constructed that will house a city worth of people and likely completely run on renewable energy which is made/recycled through the building itself. These buildings would contain housing, places of work, and leisure. These buildings could very well be the only buildings even standing within eyesight and completely redefine what we think of when we think of a city. The main form of travel to distant parts of the building will be elevators that travel not just up and down but side to side as well.
Outside the building would be mostly beautiful park lands well taken care of and made for the enjoyment for the inhabitants. Everything beyond that point will simply be left to nature with the exception of perhaps some roads. (Transportation at this point should also be with renewable energy sources and be air vehicles)
I guess this building is perhaps the first step into that direction. I wonder if the creator of this building shares the same vision of the future as me.
If collecting rainwater is "making its own water", do we do the same by using taps etc?
Where tall buildings etc sway a little in the wind, I'd be surprised if they couldn't use that somehow to generate power. There's already some manner of damping I think, so generating electricity could be a nice side-effect.