You can set your Account to be scheduler for some resource, such as a conference room, company car, etc.
When an Account LargeConfRoom@mycompany.com is created, log into that account and make sure it has the Main Calendar Mailbox created (you may want to create a test Event, and when it is being processed, the Main Calendar is created and the Event is stored there).
Then open the Rules page and create the following Process Requests Rule:
The Accept Request Rule action parses the incoming message and tries to find a Calendar Event Request or Calendar Event Cancel object in the message. If the message does not contain any Calendar Event parts, this Rule action does nothing and the next action rejects the message sending an error report to the message sender. If the rule parameter contains the [tasks] prefix, then the server looks for Task Request or Task Reply objects in the message.
If the Event or Task Request is found, the Accept Request Rule action opens the Calendar or Tasks Mailbox specified as the Rule parameter or the Main Calendar or Main Tasks Mailbox if the Rule parameter is an empty string (after processing possible prefixes). The Rule then checks that the requested event does not conflict with any other object. If a conflicting object is found, a negative Reply is sent to the organizer. The negative Event Reply contains the conflicting Event organizer's name. The incoming message is discarded, and Rule processing stops.
If no conflicting Event is found in the Calendar, the message is copied into the Main Calendar and a positive Event Reply is sent to the Event organizer. The Account Free/Busy information information is updated. The incoming message is discarded, and Rule processing stops.
You can specify the [ignore-conflicts] prefix in the Rule action parameter field. In this case the Accept Request Rule action will not check for conflicting events or tasks.
The prefix [tentative] can be also added to the parameter field so the event or task request are accepted tentatively.
You may want to grant certain persons a right to acquire a resource time slice even if it has been booked by someone else. You need to create a different Rule (for example, with the "Process VIP Requests" name) and assign a higher priority to that Rule:
If a message is processed with the Accept Request Rule action with the [force] parameter, and a conflicting Event is found in the Calendar: