Filtering interesting plurkers by distance from ZIP code or city

I'd like to see the Interesting Plurkers page able to be filtered by "X mi/km from postal code ABCDE" or "X mi/km from city Y." I'm in a large metropolitan area, searching for people in my suburb doesn't turn up a lot of different people. On the other hand, filtering plurkers from only the large city excludes everyone from ALL the surrounding suburbs.