Rendering
Flamingo
All things <a href="http://www.flamingo3d.com" rel="nofollow">Flamingo</a> related
Neon
Neon™ is a free, fully raytraced viewport plug-in for Rhino 5.
V-Ray
Topics related to the V-Ray for Rhino render engine
Iray for Rhino
Topics related to nVidia's Iray rendering plug-in for Rhino
Penguin
All things <a href="http://penguin3d.com/" rel="nofollow">Penguin</a> related
Brazil
Topics related to the <a href="http://brazil.mcneel.com" rel="nofollow">Brazil for Rhino</a> render engine