Here are very interesting photo-stories (my favorite format of blogging) from zyalt (of livejournal.com) on the life of illegal migrant workers in Moscow, Russia.  Unfortunately, they are all in Russian, but I am sure you can get the idea from the photos as well.

A walk through a dormitory, which houses 500 illegal migrants from Central Asia and some of the former Soviet countries. Most of the residents work in for the Moscow municipal Housing and Utility agency (mostly street cleaning) without official registration and get paid 3 times less than required.

Photos from celebration of the Day of Workers of Housing and Utilities sphere in Russia. Most of the workers in the housing and utilities sphere of Moscow are illegal/legal migrants from Central Asia. The story touches upon difficult fates of various people working in the big city. Photos are taken from the same blog posts.

Photos are taken from the blogs.