Pete Draper has made an 11-part tutorial on creating a tornado using Particle Flow in 3ds Max.
CGschool - Arch-Vis Training in 3ds Max, Photoshop and V-Ray
CGschool provides world-class architectural visualization training in 3ds Max, V-Ray and Photoshop.
Animator's Toolkit PathRig
PathRig is a new addition to the Animator's Toolkit that generates paths guided by target nodes.
Alessandro Cangelosi has launched r|shaders 1.0, a collection of procedural materials for 3ds Max.