Real estate overlays

This one is obvious, I just wish someone would do it. Use google earth/google maps to aggregate the following data:

MLS searches would show up as dots on my map, allowing me to do searches based on location.
Additional overlays such as
Crime
Restaurants and other businesses
Schools
Color coding cost ranges so I could visually see density of prices
Census data (ethnic makeup, average income, density of children)
Sex offenders

Additionally most cities are making plats available, so overlaying plats would also be very useful.

Real estate searching is still so damn primitive. The only downside of any real estate technology is that we are about to enter a real estate bust, so getting in may be like getting into a telecom startup in 2001.