Cacher is the code snippet organizer for pro developers

http://www.pcmag.com/article2/0,2817,2380448,00.asp

https://www.zoho.com/projects/features.html

https://basecamp.com/ (recommended by Janice Moore)

https://asana.com/ (free for 0-15 people) - recommended by Nesha 

https://trello.com/ (free with base features)

https://freedcamp.com/ (FREE and looks awesome; recommended by Erin Flynn & others in Unstoppable Basecamp FB group)

https://www.teamwork.com/ ($69/month)