The Apple Developer Connection has published a how-to article for developers to tap into the .Mac SDK. The .Mac SDK is a set of programming hooks that allow third-party developers to integrate their applications with .Mac, and the article serves as an introduction to actually applying the SDK.
"Weill cover the components of the .Mac SDK," Apple wrote in the article, "how it works, why you want to use it, and how you use it to build applications integrated with .Mac services. Finally, weill look at real-world examples of .Mac integrations, to spark your imagination about the possibilities for creating innovative new features for your own application."
The full article is quite detailed, and includes sample code and other resources. The Apple Developer Connection (ADC) is Appleis umbrella organization for developers. The ADC regularly publishes articles and other resources to help developers better develop on the Mac and iPod platforms.