We have been doing a lot of research for quality map data on homeless populations in certain areas and shelters. The data we have found is very spotty and so we thought it would be appropriate to setup a map where this information could be crowdsourced.
We started HomelessMaps.Blogspot.com as an attempt to provide better information about homeless populations and the locations of shelters in areas. In the maps above you can dynamically search based on census data of homeless populations. The 2nd map is a map of homeless shelters.
If you have any information to add to this please email me at jeff@syndicatedmaps.com.