Windows only: The popular Windows firewall application ZoneAlarm Free has a big brother called ZoneAlarm Pro, which boasts a handful of features not available in the free version—including integrated antivirus. Normally $US40, ZoneAlarm Pro will be available tomorrow (November 19 Australian) for the low, low price of free. ZoneAlarm Free was voted one of the five best Windows firewalls by Lifehacker readers, so if you like what you’ve seen from that, a free upgrade to the Pro version sounds like a winner. The promotion link below will likely offer an active link to the deal starting at 1AM on November 19 AEST.