QIWare!

RapidMiner (Community edition) is a data mining software.It was formerly known as "YALE".

Knime is a java open-source, cross-platform application which name means "Konstanz Information Miner". It is actually used extensively for data mining, data analysis and optimization. It can be downloaded as the core application itself(Knime Desktop), or the whole SDK which is based on Eclipse Helios.

Weka is a collection of machine learning algorithms for data mining tasks; with its own GUI.

SPSS is a computer program used for statistical analysis. In 2009 SPSS re-branded its software packages as PASW (Predictive Analytics SoftWare). This software puts the power of advanced statistical analysis in your hands. Whether you are a beginner or an experienced statistician, its comprehensive set of tools will meet your needs. The company announced July 28, 2009 that it was being acquired by IBM and it became "SPSS: An IBM Company".

Revolution Analytics provide commercial support and software for the open source R - the world's most powerful statistics software.