Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
SocialEngine - Socialengine PHP: Elevating Your Online Community Experience.
Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.
mooSocial - mooSocial is the best social network script to create a niche community or social site.
EssentialPIM - EssentialPIM is a free Personal Information Manager that keeps up with the times and lets you manage appointments, tasks, notes, contacts, password entries and email messages across multiple devices and cloud applications.
JomSocial - Open Source Social Networking Software. Award winning open source community software by JomSocial. This social networking software is widely used by many Joomla users.