On our last production, we had to consolidate a lot of complex sets into background renders as we were on tight deadlines. Often, the shot would need some form of contact shadow as well as masking so the obvious choice was to use the mental ray matte material. Depending on the type of shot, HD render times could be cut from 10 minutes per frame to around 45 seconds, with no perceptible loss of detail or quality.
I wrote a utility that allowed the user to browse for the rendered backgrounds and quickly set the material up as a matte material, ready to be assigned to the background objects and rendered.
The interesting thing about this? Using HitchHiker allowed me to write this on my train ride home one day, so it's to illustrate how the built in functionality of a custom dotnet control can speed up the deployment of production scripts. Hope you find it useful!