Here is a tutorial on using Motiva COLIMO 1.7, a realtime postproduction tool with native Vray 2.4 support.
Motiva Exposure Control for V-Ray
Motiva have released a free plugin for 3ds Max that serves as an extension over V-Ray's native Exposure Control.
Making Gravel with MultiScatter
Alexey Duk has posted a tutorial on how to create gravel with VrayPattern and MultiScatter in 3ds Max.