Dingtone - Dingtone is a free call and texting application for making unlimited calls and text messages to any number at the moment registered in any part of the world by any cellular company.

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.

Textnow.com - It lets you text your friends, aka my only source of happiness

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

FluffyChat - Open. Nonprofit. Cute ?

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