Ettercap - Ettercap is a suite for man in the middle attacks on LAN.
Calendly - Say goodbye to phone and email tag for finding the perfect meeting time with Calendly. It's 100% free, super easy to use and you'll love our customer service.
tcpdump - tcpdump is a common packet analyzer that runs under the command line.
Acuity Scheduling - Automate your client bookings, cancellations, reminders & payments using the worlds friendliest online scheduling software.
Wireshark - Wireshark is a network protocol analyzer for Unix and Windows. It lets you capture and interactively browse the traffic running on a computer network.
Doodle - Make meetings happen. With Doodle, scheduling becomes quick and easy.