Open source note taking and to-do app with synchronization
Machinery is an asynchronous task queue/job queue
An open-source, self-hosted memo hub with knowledge management
sleek is a todo.txt manager, free and open-source (FOSS)
Simple Online Planning
Free flexible open source todo manager featuring hierarchical tasks
IGSuite is a web-ajax-based Integrated Groupware Suite
A simple task planner: quickly add, edit, and delete tasks.
So much to do, so little time...
The Freeplane add-on that syncs a GTD mind map with a todo.txt file
a free mind mapping tool, to especially assist decision making
Windows Companion for the Android App Denkzettel
Easy to set up bug tracking with Java
A simple but useful list for storing tasks
Custom, simple, timed audio and visual reminders using cron scheduling
Freeplane add-on for task management and memo taking
Small Business Appliance
simple php/mysql project management system for sustainability planning
All your favorite services in one place
QNC is a command line interface app for creating quick notes
A note taking program with WebDAV sync
Create sticky notes, to-do list, journals & reminders all in one app
Program for manipulating with mind maps