Training Suggestion: What module of SAP should start with

I am a senior technical consultant currently working for an IT consulting/service/developer company. I am an M. Sc. in Computer Science and System Engineering with 15+ years of experience. Recent assignment with Performance Measurements and Testing project for HR and CRM applications of a public corporation encouraged me to get trained with SAP.

But I don't know from where to start ?

Here is a summary of my skill sets:

- Applications and Test tools development in JAVA and C (mostly Linux based)

- Interface development for load testing of Web Services using SOAP-UI (Linux based)

- Performance test development of web based and SAP applications using HP VuGen (Loadrunner)

- Embedded system development using C, VxWorks

- Expert in UNIX (Linux), MySQL

Recent interaction with SAP:

- Performance test development for an HR and CRM modules (entry through web portal)

I would prefer to stay within technical arena. Please suggest me which module of the SAP should I start with for a formal training.

Thanks.