ZoneAlarm blocked what was most likely a port scan by a remote computer trying to find out if you are running a remote administration tool. The scan attempted to communicate with port 1680 on your computer, which is typically used by Carbon Copy (a common remote administration tool). Though, ZoneAlarm has determined that you are not currently running Carbon Copy on your machine.
Must be those anti-wiretapping libertarians. They always like to brag about what accomplished computer hackers they are.