Check out this awesome NY Times article on architecture and design to overcome social problems.

My mum used to talk about some of my tinier friends as 'pocket people' (she's imaginative), and said that they would save the planet by not consuming as much space, food, everything. Pocket People would fit really well in these houses depicted in one of my favourite architecture books: Tiny Houses by Mimi Zeiger, but normal sized people fit in there too! You can check out why Tiny is important here.
A lot of the houses depicted are surrounded by nature, and really make the most of space (and are unutterably beautiful). Using space wisely and frugally is going to be a big issue very soon (well, it's already one now, really!). Maybe architecture has some answers.

And if you're an architecture nut, or you just love the idea of creating habitats that link back into nature, check out Green magazine.