RapidMiner - RapidMiner is a software platform for data science teams that unites data prep, machine learning, and predictive model deployment.
Apache Mahout - Distributed Linear Algebra
KNIME - KNIME, the open platform for your data.
WEKA - WEKA is a set of powerful data mining tools that run on Java.
RStudio - RStudio™ is a new integrated development environment (IDE) for R.
Scikit-learn - scikit-learn (formerly scikits.learn) is an open source machine learning library for the Python programming language.