Four open source alternatives to Pentaho Community
BIRT (free BI suite) is an open source software project that provides the BIRT technology platform to create data visualizations and reports that can be embedded into rich client and web applications, especially those based on Java and Java EE. BIRT is a top-level software project within the Eclipse Foundation.
JasperReports (free BI suite) Server is a stand-alone and embeddable reporting server. It provides reporting and analytics that can be embedded into a web or mobile application as well as operate as a central information hub for the enterprise by delivering mission critical information on a real-time or scheduled basis to the browser, mobile device, printer, or email inbox in a variety of file formats. JasperReports Server is optimized to share, secure, and centrally manage your Jaspersoft reports and analytic views.
ReportServer provides an extremely flexible open source reporting and dashboard environment. It supports Eclipse Birt, JasperReports and SAP Crystal Reports reporting engines in addition to its own ad-hoc oriented reporting tools. The user interface is web based and it supports a wide range of admin tools.
SpagoBI (free BI suite) is essentially a very large collection of open source software brought together to create a broad business intelligence capability. In fact it goes beyond the traditional notion of BI to embrace domains such as data mining and BPM.