Blender Rigify to Unity Ragdoll
Some files to help you along:
Open your model or the one provided in Blender. Make sure the rigify add-on is enabled in Blender by going to User Preferences, hitting the Add-on's tab and typing rigify to bring it up
On your mesh hit Shift-A and select Armature > Human (Meta-rig) from the menu. You might need to move and adjust your meta-rig so it lines up nicely.
With the metarig selected switch to armature and then under Rigify Buttons at the bottom select 'Generate'. It might take a little bit to generate your rig.
Deselect your rig by hitting 'A' then select your mesh and then your rig and hit Ctrl-P and select 'With Automatic Weights'.
Delete all of the WGT items that Blender generates.
Open up a Unity project and add your .blend file to a scene. Then, open the Ragdoll wizard by right clicking on your object selecting 3D Object and hitting Ragdoll...
Assign your bones as shown here and click create when you are done.
Enjoy your new ragdoll - you might need to make some adjustments in Unity to get it looking exactly how you want, but it's a good start.