Set A Light
I recently bought a copy of Set a Light software to enable me to test and model lighting setups before going to the studio. I have found it to be an amazing bit of software allowing you to move lights around attach different modifiers, play with power settings and rotate around the studio in 3D to see what is going on. When you are happy it will output a vast range of information in multiple formats including a test photo, set up diagrams to which you can add dimensions. There are a selection of models which you can change attire and pose, some even have an auto pose in which they move through a sequence of poses.
I have found this very useful for researching lighting setup and outputting images for my blog to explain what I have been doing.