Personally, I think we should give urban homesteading visas. There are thousands of abandoned properties in Detroit. We should give people visas and the property if they live there 5 years.
This is creating real demand by giving immigrants away something at little cost to the United States to raise the demand of all of our housing. On a secondary note, I think, it is beneficial to award more visas to qualified foreigners to reside in the country.
Seriously though, they have a hard time giving away land in Detroit. There are some people/organizations that are trying in earnest to "bring the city back". -The infrastructure for a vibrant city exists. http://www.freep.com/article/20110920/BUSINESS04/109200384/D...
The best proposal I've seen is to seize distressed properties and flip the mortgage back into a non-profit federal holding company that takes whatever reasonable payment you can afford (presuming you can afford a "reasonable" payment) and calls it "rent." If, after inflation has taken your mortgage back above water, you wish to purchase your house, your rent paid counts against it. If you want to move somewhere else, the house isn't beat to shit because you've been living there. The US Government ends up "owning houses" rather than "insuring mortgages" but in the end, don't they anyway?
http://online.wsj.com/article/SB123725421857750565.html Further discussion: http://www.johnmauldin.com/frontlinethoughts/solving-the-hou...
I linked simply because this is an idea that economists have put forth for a couple years now and the article was light on discussion.