Trello

I tinkered with Trello a bit yesterday and saw some uses for it.  It is an easy way to make and share a collaborative task list.  I found the introduction helpful as a place to start.  I simply created a list of the things I need to do or have done in preparation for my trip to Florida.  It was easy to develop the list of tasks and sub-tasks. 
It is not  replacement for Microsoft Project or other such high end management tools.  Trello does not have all the scheduling tools and I do not believe it would interface with Microsoft Office tools the way Project does.  But neither does it take extensive time and effort to learn.  It would be very good tool for managing a collaborative group project in a class, where various learners can ensure all tasks are completed.