Dudle - Dudle is an online scheduling application, which is free and open source.
Task Muncher - Task Muncher is a cross-platform and web-based application that is designed to organize and keep the track of everything and focus on munching the weekly tasks.
FullCalendar - FullCalendar is an open-source JavaScript event calendar.
OnSched - OnSched is an appointment setting software with many other features.
Framadate - Make your polls
Motion Firefox - All-in-one time management tool in Firefox