doo - A smart, simple app for reminders and to-dos
Google Groups - Google Groups allows you to create and participate in online forums and email-based groups with a rich experience for community conversations.
Purp - A smart to-do list and goal tracker app
Galette - Galette is a membership management web application towards non profit organizations.
Gone - An ephemeral to-do list
Bigtent - BigTent is a web-based organization and communication portal for groups.