Ok, like a lot of people I find it fascinating to browse Zillow and see the estimated values of my neighbour's houses, and yes, I admit it, my friends. Another example of the little shock you get when data that was always technically public becomes truly public thanks to some new internet application.

Of course Zillow is adding to the data, by taking the public info (house sale figures, house size and features from county records and MLS) and applying algorithms to guess current values. However, they're often quite innacurate. High for my house, way low for a number of others I checked. (Diane Feinstein's new house, which just sold for $16 million, shows as only around 5 million. I wonder if she played some tricks to keep the value out of the records?)

Anyway, as this data becomes more available it would be nice to do other things with it. The idea I thought about was a something like a topographic map, so you could soar, Google Earth style, over "hills" of high value. Or plot other metrics like cost per square foot etc. Might also help people neighbourhood shop, and an interesting lesson in real estate capitalism.