Maybe more like a feature... I've noticed that realtor.com beta lets you search for houses within an X-mile radius of a given address (e.g. your work). Trulia.com, on the other hand, lets you see the housing trends for a given city/zipcode. If I could do a search on Trulia (and save it) within X miles of an address, and see housing trends and houses for sale for that circle (while I'm dreaming, let me have a custom RSS feed for a given search instead of an email), that would be ideal.