When I do information design, I usually look for data that tells a story so plainly, that it seems blunt, almost a little rude. This is where Zillow comes in. It has some really blunt data. How about the value of your home trended over the past 10 years, against average homes in your zip code, city, and the United States?

But here’s what you really want to see. An aerial photo of your street, with the price of your neighbors home superimposed on their roofs. Now that’s explicit.

If this was accurate, it would really be freaky. The value of our home at the time I bought it is off by about 15%.
Update: I found one that’s accurate. The interface is not as good, and no maps. But the numbers are based on sales and city appraisals.