Task Management - Mind Mapping Tools

WorkFlowy
WorkFlowy is a list-maker. It’s also a wonderful planning tool, helping you to create detail-oriented notes, brainstorm ideas and manage your tasks. There is a collaborative element to Workflowy as well, allowing you let others view or edit any WorkFlowy task with a unique URL for every task.
HiTask
HiTask allows you to track time and manage your to-do list with an intuitive and easy-to-use tool that will save you time and a lot of frustration.
Nirvana
An app for task management based on the GTD book by David Allen for getting things done.
Doodle
Scheduling tool that allows the user to “poll” a number of people to determine at what time they could attend a meeting, event, etc. Users create a poll with date and time choices for the participants to choose.
Pegby
Set up like a corkboard with index cards stuck to it. The corkboard has three columns to place your index cards on. A column for things to do, a column for things in progress, and a column for things that are done. Each of index card can be assigned to a person, can have files attached to it, and can have due dates assigned to it. You can use Pegby as an individual or you can share your corkboard with others

Toms Planner
A simple drag-and-drop, Gantt-chart-based, online planning tool
Gantter
Provides Gantt chart project planning and much of the basic functionality of Microsoft Project for free. Considering that it is emulating a very complex desktop app, it works surprisingly well.

MindMeister Mind Mapping 
A powerful tool that is great for mind-mapping on the go.  MindMeister keeps all your mind maps in the cloud for easy access. Because of this, it allows you to collaboratively build your mind map with others. 
bubbl.us
Enables users to create mind mapping and brainstorming diagrams online. To begin, the main topic/concept is entered in to the parent bubble. Then ideas and thoughts are recorded in colorful text bubbles linked to the parent bubble. Users continue to add text bubbles which are color coded according to hierarchy. 
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