Google Calendar - Spend less time managing your day & more time enjoying it
Teem - Cloud-based meeting room booking system
Microsoft Outlook - Organize your world. Outlook’s email and calendar tools help you communicate, stay on top of what matters, and get things done.
Meetio Room - Meeting Room Booking System
iCal - In Calendar on your Mac, subscribe to calendars published or shared by others.
BOOKMEETINGROOM.COM - Book Meeting Room - Conference & Meeting Rooms Management