Trello - Infinitely flexible. Incredibly easy to use. Great mobile apps. It's free. Trello keeps track of everything, from the big picture to the minute details.
Notational Velocity - Notational Velocity: modeless, mouseless Mac OS X note-taking application
Asana - Asana project management is an effort to re-imagine how we work together, through modern productivity software. Fast and versatile, Asana helps individuals and groups get more done.
Evernote - Bring your life's work together in one digital workspace. Evernote is the place to collect inspirational ideas, write meaningful words, and move your important projects forward.
Infinity - Infinity is a fully flexible work management platform where you can organize all your work, your way.
Notational - Notes at the speed of thought