IBM developerWorks' Frank Abelson has published a tutorial on using XML parser to build a RSS reader from scratch. Abelson has started with the basics of RSS and gone in detail to explain each aspect of the app. If your looking to learn something about SAX and HTTP, this tutorial can help alot. If you have been developing for Android, don't worry about the requirements.
Heres a screenshot of the RSS reader Abelson made,
Its available as a PDF file or online here along with the complete source. You have to register first though.