CalendarToSlack automatically sets your Slack status and availability according to events on your Outlook calendar. It updates your Slack availability to Away whenever you have an event, and updates your Slack status to a custom status/emoji that's specific to the calendar event. Check out the Wiki for features and documentation.

The application is still very much a beta. For questions about anything (installation troubles, how things work, problems), feel free to file an issue; I'm happy to chat through things!