Communifire - Enterprise Social Collaboration Software
Todoist - Todoist is a to-do list that helps you get organized, at work and in life.
Bonzai Intranet - Bonzai is an intranet platform with flexible pre-built features for SharePoint and Office 365.
Todo.txt - Track your tasks and projects in a plain text file, todo.txt. A todo.
hub - The Hub is a versatile intranet portal and collaboration solution that boosts employee engagement and productivity in a digital workplace.
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.