Download of BusySync 2.3.1 for Mac was on the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The software belongs to Productivity Tools. This Mac app is an intellectual property of BusyMac LLC. According to the results of the Google Safe Browsing check, the developer's site is safe. Despite this, we recommend checking the downloaded files with any free antivirus software.
From the developer:
BusySync allows multiple users to share and edit iCal calendars on a local area network and sync iCal with Google Calendar. BusySync is a Mac OS X System Preference Pane that runs in the background and adds calendar sharing capabilities to iCal. Leveraging Apple Sync Services and Bonjour, calendar events created in iCal are instantly synchronized with other iCal users on the network and with Google Calendar.
You may want to check out more Mac applications, such as iAlarm, MenuCalendarClock Entourage or Chronos, which might be similar to BusySync.