From BlenderWiki
Multiple custom Addon/settings locations (e.g. workgroups in Nuke/Softimage/Max)
Integrating Blender into a pipeline eventually means you have to be able to roll out plugins/addons to the team and make sure everyone uses the correct versions, settings, etc.
You might even need different setups for different projects. This is where workgroups come in quite handy. Let’s say you have a Studio-Workgroup that everyone is connected to, that supplies some everyday-use custom addons and presets, and a workgroup that loads some stuff that is only needed for the project you are currently working on. Maybe you also even have your personal workgroup in a dropbox folder with all your personal tools,keymaps,whatnot so that you have them accessible everywhere.
Many studios have custom launchers for their applications, that connects the right workgroups and creates the right bookmarks inside the application. Also blender could detect environment variables to determine if it should read a custom directory instead of the default one. That behaviour is quite usual in industry pipelines.
To give a real life example:
Some time ago I wanted to render something on our renderfarm, but I was using an external renderer (mitsuba) that wasn't installed on the farm machines. There are hacky ways how you can get it to work, but none is convenient. With Softimage for example I would just pass "-w <workgroup-directory>" as a commandline parameter and all machines would load all addons from that directory.
Solution
Add a place to insert Workgroup locations to the preferences-UI (see mockup below), and add a commandline flag to pass workgrouplocations (e.g. -w "//foo/bar/Workgroup;/home/bla/myworkgroup;/path/to/another/workgroup"). All addons and startupscripts will be activated automatically.
