Gone - An ephemeral to-do list
Day One - A simple journal application for the Mac, iPhone, and iPad. AboutTo learn more about Day One, see these two excellent reviews . PublishPublish is not available in Day One 2.
Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
Stigma - A daily journal to be happier and more self-aware
Check - Check is a unit testing framework for C, which runs on environments such as GNU/Linux, GNU/Hurd, BSD, and Mac OSX.
Fabric - The story of your life that writes itself