For those of you who are interested in the housing section of craigs list, there is an interesting website you should consider using. Housing Maps, which is written on the google maps api, plots all the rental houses/houses for sale/rooms/sublets on the Google map. Nicely done i must say. All the rental houses/houses for sale/rooms/sublets data is picked from CraigsList database.
   All the filtering options  which you find on cragislist is available here. Filter by city/price/number of rooms/ etc. Keyword seach is AJAX enabled and your search almost instantly pulls out all the results on the right hand side of the map and the map refreshes to show you the latest data.

CraigsList got popular cause of its simplicity, you bet HousingMaps would complement CraigsList on this. The only thing i didnt like about this site is they do not show the latest list of houses available on the craigsList. May be there could be a database synchronization issue between the craigslist and housingmaps, that they need to work on.

But overall its just perfect!