Web services are a great way of relying on external components that exist on the web for various parts of your application that would be tedious for you to write. These videos should help you get started with some of the most popular services on the web today.
RESTful Delete with SLIM, jQuery and JSON
Adding jQuery RESTful calls for using the DELETE verb when deleting items via a JSON REST interface.
SLIMming Out Your Controller
An introduction to the SLIM PHP framework. This sinatra-like php framework is a great tool for simple JSON endpoints and light server-side application development.
Consuming RSS Feeds with Zend_Feed_Reader
Quickly and easily consume an RSS feed with Zend_Feed and then filter the result set.
Creating RSS & Atom Feeds with Zend_Feed
Use Zend_Feed to build a simple RSS / Atom feed from a dataset in your models.