Know Where You Live
Know Where You Live was the runner-up in yesterday's Australian GovHack. The site provides a wealth of local information about Australian neighbourhoods.
To use the site users simply have to enter their postcode (try '2000') and Know Where You Live returns demographic information, income levels, rental returns and crime statistics for the area. What I like most about this site, however, is the use of a Google Map as a header to the page, with the name of the district superimposed on top.