Matthieu Fiorilli from http://www.cgaddict.com has just released v2.0 of fStretch for Maya as "Donation Based" under a GNU General Public License.
"The idea behind the plug-in is to be able to drive blendShapes that are turned on and off based on the tension and angle change that happens on a geometry. These blendShapes are sculpted to adjust the deformations."
The plugin is nicely integrated into maya, comes with well written documentation and is multi-threaded.
Not only that, Matthieu has put together a series of videos showing usage examples, code explanations and "how-to" tutorials for compiling windows, osx and linux versions, making it an amazing resource for anybody interested in learning how to write C++ deformers for maya.
For the full story, head over to cgaddict.com.
My compilations for maya 2014, 2015 and 2016 (windows) are available on my downloads page.