UserVoice - UserVoice integrates easy-to-use feedback, helpdesk, and knowledge base management tools in one platform that empowers users to speak and companies to understand.

Roadmap - Collision avoidance for projects and people

Freshdesk - Freshdesk is a cloud-based customer support software that lets you support customers through traditional channels like phone and email, social channels like Facebook and Twitter, and your own branded community

Due.work - Simplify your work, to-do's and communications

Zendesk - Zendesk is a beautiful, lightweight help-desk solution.

Frill - A better way to collect customer feedback