IIS Web Deploy (keeping a webfarm in sync)

http://www.iis.net/download/WebDeploy

Web Deploy allows you to efficiently synchronize sites, applications or servers across your IIS 7.0 server farm by detecting differences between the source and destination content and transferring only those changes which need synchronization. The tool simplifies the synchronization process by automatically determining the configuration, content and certificates to be synchronized for a specific site. In addition to the default behavior, you still have the option to specify additional providers for the synchronization, including databases, COM objects, GAC assemblies and registry settings.