We just launched a hosted wiki service called Miki that can be customized in this way. You can control page content by setting up custom groups and permissions

We just launched a hosted wiki service called Miki that can be customized in this way. You can control page content by setting up custom groups and permissions and you can integrate with other APIs to do things like get user settings from another source. We'll have an offline, desktop version soon. http://miki.mimix.io http://miki.mimix.io