While Reclaim is only for Google Calendar users today, you can sync your non-Google calendar to your Google Calendar. Reclaim will use your Google authentication as a way to gain access to your non-Google calendar.
Some fallbacks in using this method are known issues around refreshing—it can take up to 24 hours for changes on a shared calendar from iCal or Outlook to reflect in Google.
To connect a non-Google calendar
Make sure the calendar you want to connect is shared with your Google account that you are using to for Reclaim.
Here are resources to sync common calendars to your Google Calendar:
Once you've connected your non-Google Calendar, visit Sync your shared calendar for instructions on how to sync your Google shared calendar to Reclaim.