Letsfind - Letsfind is a fast, easy-to-use, ad-free way to create online (meeting) polls.
Cvent - Cvent's event management software provides event planners with a complete solution to increase event attendance and decrease event costs.
CozyCal - Online appointment scheduling
Eventzilla - Eventzilla lets you sell tickets online and manage attendees from one integrated application.
FullCalendar - FullCalendar is an open-source JavaScript event calendar.
Attendify - Develop relationships at the events that you attend by creating smaller events with just a few people.