LTSP - The Linux Terminal Server Project adds thin-client support to Linux servers.
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.
Thinstation - Thinstation is a basic and small, yet very powerful, open source thin client operating system...
Acuity Scheduling - Automate your client bookings, cancellations, reminders & payments using the worlds friendliest online scheduling software.
Nakama - Nakama is an open-source distributed social and realtime server for games and apps.
Doodle - Make meetings happen. With Doodle, scheduling becomes quick and easy.