I Need Closure(s)

Just your run-of-the-mill Google Maps page, except for a couple of things; the server part is in Portable AllegroServe (no big deal), and the addresses came out of my Mac's Address Book via OpenMCL (a bigger deal).
I got interested in this after hearing an O'Reilly "Distributing the Future" podcast where someone mentioned that not everyone will want all their information on the web and there will be applications where part of the data is on the web and part is kept in the user's local storage.
The basic understanding of the Mac's AddressBook library came from this Mac Dev Center article, and help from Gary Byers got OpenMCL loading and searching the Address Book in OpenMCL. The rest is basic Portable AllegroServe.
The geocoder I'm using is Ontok, which has a REST api that takes up to 10 addresses at one time and returns CSVs that start with latitute and longitude co-ordinates.
Wil Shipley mentions that instead of using a database for storing customer orders he keeps them in XML files and uses Spotlight for searching. Something similar could be done with Address Book, just keep addresses in the built-in library instead of a database.
Code is here if you'd like to see.