If you live in the USA (or would just like to check out a neighborhood in the USA), fill out the form at…

http://www.instagis.com/

then click to…

http://www.instagis.com/infographics

and fill in your address. It will, among other things, tell you the average income/year for your entire state, then tell you the average income for those living within 1 mile of your address. VERY interesting to plan community outreaches. (Thanks Caleb!)