I remember years ago hearing about a project called Arcosanti, whereby an Italian architect Paulo Soleri was building a small prototype city in the Arizona desert. From the website it would seem that his work revolves around high density and multi-use facilities built along ecological principles. A percentage of the site is already built and the public spaces in particular look quite interesting. The project has been underway for around 30 years and they are still a long way off being finished by the look of it.
Soleri seems to be very optimistic that good design can positively affect social interaction. Some of his designs are quite arrestingly poetic in scope and scale, but I'm curious as to what it would be like to actually live in such a planned city. Living in a high density community is one thing when it is a campus of like-minded architecture students motivated with a single goal. What happens though when the Jones's with their late night parties and Sunday morning screaming matches end up cheek-by-jowl next door?