Developing SAP DB
Developer information from Daniel Dittmar.
MaxDB
An open, SQL-based, relational database system that provides high availability and performance scaling from small to very large implementations. [Open Source, GPL/LGPL]
Sap DB Developers's Site
Developer Helper Site with actual setup guide for linux and information about the project.
SapDB Wiki
Collaborative hypertext environment, with an emphasis on easy access and modification of information.