Postal

Provides a form element for postal addresses. This permits any module to use a consistent postal form for processing, validation, and storage of any mail address. This module includes the Postal Field module, which allows you to add postal addresses to you CCK Content types.

While it's useful to have a postal address field on your nodes, it's also valuable to have postal elements on user pages, ecommerce transactions, address books, or integration with third-party data. Modules that support the postal API will be able to manage their own storage for addresses while using a common UI for presentation, validation, etc.