This is a perennial topic on a very basic necessity: keeping multiple instances of an application synced across a farm of servers. What are the options? Free? Paid? How about syncing IIS settings?
You could use Web Deploy or Robocopy for that task.
Web Deploy (IIS)
Web Deploy (Web Deployment Tool) simplifies the migration, management and deployment of IIS Web servers, Web applications and Web sites. Administrators can use command-line scripting with Web Deploy to synchronize IIS 6.0 and IIS 7.0 servers or to migrate an IIS 6.0 server to IIS 7.0.
Robocopy (Wikipedia)
Robocopy, or "Robust File Copy", is a command-line directory replication command. It has been available as part of the Windows Resource Kit starting with Windows NT 4.0, and was introduced as a standard feature of Windows Vista, Windows 7 and Windows Server 2008.
See this article for a comparison between Web Deploy and Robocopy:
See also these articles for more information about Robocopy and syncing IIS: