New Machine Learning API's to Explore

Today on reddit, someone asked about freely available machine learning API's.

Before the list gets buried, I'm duplicating the contents of that thread here for future exploration:

Weka - Java based ML API
http://www.cs.waikato.ac.nz/ml/weka/

Toolkit for Advanced Disrimnative Modeling
http://tadm.sf.net/

Mallet - Java based ML API
http://mallet.cs.umass.edu/

WekaUT - An extension of Weka that adds clustering
http://www.cs.utexas.edu/users/ml/risc/code/

LibSVM - SVM API
http://www.csie.ntu.edu.tw/~cjlin/libsvm/

SVMlight - A C API for svm
http://svmlight.joachims.org/

C++ API for Neural Networks
http://github.com/bayerj/arac

Torch5 - A Matlab-like ML environment
http://torch5.sourceforge.net/

R - Open source statistical package that can be used for ML
http://cran.r-project.org/web/views/MachineLearning.html

pyML - Python API for ML
http://pyml.sourceforge.net/

Rapidminer - Open Source Data Mining Tool
http://rapid-i.com/wiki/index.php?title=Main_Page

Orange - An Open Source Data Mining Tool (Python and GUI based)
http://www.ailab.si/orange/

Glue - Open Source API for reinforcement learning (Can be used with multiple languages simultaneously)
http://glue.rl-community.org/wiki/Main_Page

Vowpal Rabiit - Learning API from Yahoo Research
http://hunch.net/~vw/