I have an enterprise farm where users have multiple site collections that they have created. They have the same set of users in a group that need to have group permissions assigned across multiple site collections. These are massive groups, so non-trivial to manually create and keep synced.
I know AD groups represent the logical solution. Due to enterprise limitations, that won't be possible.
Is there any way to allow permissions groups to be shared across site collections in a web app? Perhaps some CodePlex code or third party commercial web part that would facilitate this?