iCal Archiver increase the performance of iCal by archiving old events.
If you've been using a Mac for years, you probably have hundreds or thousands of old events stored in iCal. All of that legacy data can bog down iCal and make it slow. And if you're syncing your calendars with others using BusySync, you're probably slowing them down too.
You can significantly increase the performance of iCal by archiving these old events using iCal Archiver.