RenderMan, developed by Pixar, used to be the top pinnacle of rendering engines for studios to use to create their movies. With the ever evolving progress of technology, other engines have grown, such as VRay, Arnold, Maxwell, Mantra, and studios are able to choose different engines to meet different needs and budgets. Undoubtedly though, RenderMan is still one of the top industry standards and is a great tool to learn for surfacing, shaderwriting, and lighting. Unfortunately, RenderMan used to be hard to get your hands a copy on if you're not a large studio or facility and are just learning or want to do some R&D. Recently Pixar just announced that RenderMan is having a price restructuring of $495 per license or free for non-commercial use (evaluations, personal learning, experimentation, research, and the development of tools and plug-ins for RenderMan)!
Given the continually falling price of computing, trends point to studios and individual artists needing more and more rendering capacity. Reducing the cost of RenderMan makes it more cost effective to expand capacity and generate higher quality pixels. Pixar has established a new price point to specifically encourage accessibility and remove barriers to growth.
Free non-commercial RenderMan will be availabe with the upcoming release of RenderMan scheduled in the timeframe of SIGGRAPH 2014. All you have to do is register for free and you will be notified when it becomes available.