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.

PlanBox - Finally an agile management tool all teams can share, whether Scrum-savvy or not.

Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.

Crowdicity - Idea management software for smart organizations.

Task Coach - Task Coach is a simple open source todo manager to keep track of personal tasks and todo lists.

Sideways 6 - Sideways 6 is the best way to involve your employees in innovation.