Weka plugins
Weka is a great toolkit for machine learning research and applications. It includes several standard machine learning algorithms and also has the option to install custom packages which extend the functionality of the program. I have written three packages for Weka to date.
IntraClassClustering.zip
Implements the Intra-Class Clustering algorithms described in K.D. Feuz and D.J. Cook. "Modeling Skewed Class Distributions by Reshaping the Concept Space" Proceedings of the Thirty-first AAAI Conference on Artificial Intelligence 2017
MacroMetrics.zip
Implements several Macro-averaged machine learning metrics commonly used in information retrevial
RemoteExperimentExtensions.zip
Extends the Remote Experiment options of Weka to allow for greater granularity in the dividing up of tasks between workers.