I recently came across this map posted on Twitter by Max Galka of Metrocosm.com. It shows a map of the U.S. with the land area of each of the individual counties being substituted by the total market value of the housing. Keep in mind that this is the sum of the values for each county, which is going to be skewed by population; nevertheless, this GIF is way too cool not to share.
Also, I would love to see this type of map that separates out all of the Chicago neighborhoods and suburbs. My guess would be the North Shore, downtown and Lincoln Park in Chicago, and the Hinsdale/Oakbrook area would be the largest.