Hey I recall Trulia used to have heat maps that showed Sales Price, rent prices, etc on heat maps that were local.

They were really useful but they were remove when Zillow bought Trulia.

Does anyone use a heat map that shows Sales/rent prices, home values etc?  On a zoomed in micro perspective.  They usually work with google maps?

I also use www.city-data.com for heat maps that show color gradiant for maps for median household income, demographics etc.