Mix Life!
The people down -there-

http://massappeal.com/bruce-lee-the-king-of-romanias-underground-heroin-society/

http://hongwrong.com/kowloon-walled-city-photos/

The most densely populated area ever to exist, largely given up on by any major government that could claim jurisdiction over it. However, in the absence of government regulation, the citizens of the makeshift city formed tightly woven communities to improve the quality of life for all residents, making it a surprisingly comfortable place to live despite the issues with overcrowding and sanitation. It was, of course, a hotbed for crime, but criminal activity declined substantially in its later years.

I think my idea version of the "Mix" isn't cutthroat gangers and drug lords doing as they please with a helpless populace, but a tight knit community that makes the best for themselves in the absence of the amenities afforded to the "haves".