shaders_p 3.3.1 - free set of shaders for mental ray with source code.
I had write these shaders for my purpose and share it.
shaders_p works with mental ray stand alone and all common 3d softwares: Maya, 3DSMax and XSI.
shaders_p compiled for all common platforms: windows32, windows64, linux64 and macOSX.
You may download shaders_p here: http://www.puppet.tfdv.com/download/shaders_p_e.shtml
If you have SVN installed you may download latest development version here: http://sourceforge.net/projects/shadersp