[Zope] searching by miles from __ zip code

[Bill Bell]

Dylan Reinhardt <zope@dylanreinhardt.com> wrote, in part:
> But if the purpose of this is to get some proxy for driving distance,
> there's no compelling reason to be any more accurate than within a mile
> or so... distance "as the crow flies" is only a bare approximation of
> driving distance anyway.

Ignoring the third dimension--which, I imagine, becomes significant only in 
mountainous or hilly terrain--for some range of distances driving distance will be 
somewhere between the "best-case" L(2) (as-the-crow-flies) distance and the L(1) 
(Manhattan) distance.

Bill