The Open Source Data Warehousing does a great job at identifying OSS components that could be used to build a Data Warehouse stack: Infrastructure (servers, OS, databases), Integration Management (ETL, EAI, etc), Information Management (DW/Mart/ODS, OLap Servers, etc), Information Delivery (Portal, Dashboard, Analytics/OLAP Client, etc). Here is a summary:
Open Source BI/DW Projects
BI and Analytics
- BEE – http://bee.insightstrategy.cz/en/index.html
- BIRT – http://www.eclipse.org/birt
- JasperSoft – http://www.jaspersoft.com
- MarvelIT – http://www.marvelit.com/dash.html
- OpenI – http://openi.sourceforge.net
- OpenReports – http://oreports.com
- Orange – http://www.ailab.si/orange
- Palo – http://www.palo.net
- Pentaho – http://www.pentaho.com
- R – http://www.r-project.org
- SpagoBI – http://spagobi.eng.it
- Weka – http://www.cs.waikato.ac.nz/~ml/index.html
- VitalSigns – http://vitalsigns.sourceforge.net/
Databases
- http://greenplum.org (bizgres)
- http://www.ingres.com
- http://www.mysql.com
- http://www.postgresql.org
- http://www.enterprisedb.com
Integration
- Apatar – http://www.apatar.com
- CloverETL – http://cloveretl.berlios.de/
- JitterBit – http://www.jitterbit.com/
- KETL – http://www.ketl.org
- Octopus – http://www.enhydra.org/tech/octopus/index.html
- OSDQ – http://sourceforge.net/projects/dataquality
- Pentaho – http://www.pentaho.com
- Red Hat – http://www.redhat.com
- Saga.M31 Galaxy – http://galaxy.sagadc.com
- Talend – http://www.talend.com
- SnapLogic – http://www.snaplogic.com
I recommend browsing the presentation. Good stuff.