WPMU Plugin commander is a Plugin management plugin for WPMU (say that 10 times :) ).

it adds some necessary functionality to WPMU, which is missing from the official release, such as:

  1. Mark any plugin in the plugins directory to be automatically activated for new blogs.
  2. Mass activate or deactivate a plugin for all existing blogs
  3. Choose which plugins users can activate and deactivate through Manage->Plugins, for this to make sense you need to disable the built-in plugins menu (through Site Admin->Options->Menus)
  4. Activate and deactivate plugins for specific blogs, even if the user is not allow to activate the plugin.

No WPMU site should ever be without it!
Screen shots (click for full version):

Administrator menu:

User visible menu (accessed as site admin) :