Things - Things is an easy to use task manager.
Motion Firefox - All-in-one time management tool in Firefox
Week - Task management tool with a heavy focus on planning
Taskable - Using multiple work apps leads to tons of context switching, breaking flow and killing productivity.
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.
My Desk - A smart task manager for freelancers