Think the Housingmaps mashup of Google Maps and craigslist was cool? Greg Sterling points us to Redfin, which combines satellite maps and MLS homes data for the Seattle area. Says Greg:

You can see it coming: Someone is going to potentially create a Redfin nationally with Google Maps before Google. For its part, Yahoo! should integrate maps into its real estate vertical. The folks that can tackle this on a national scale will create an enormously powerful (and lucrative) vertical. Portals, search engines, real estate verticals (e.g., HomeGain) and, especially, newspapers take note.