Collaboration between team members, work lists and item lists, and data export are my main use cases for Sharepoint 2010 on Windows server 2012r2-24x7. There are some Sharepoint custom apps that have been created as well.
Regarding collaboration in Sharepoint 2010 on Windows server 2012r2-24x7, messages are passed between team members through posts and replies to track progress on different work items. For the custom apps, one in particular was created for the MRI department where a custom list was established so users could request access. It is called badge request access, and there is a workflow for approval by senior staff.
The main use cases in Sharepoint 2010 on Windows server 2012r2-24x7 have been primarily for custom apps for different access requests, particularly the previously mentioned badge access application and for requesting access to other resources. Different Sharepoint groups were controlled through Active Directory, and information for each separate team was controlled by access through Active Directory.