RingCentral - RingCentral is the leading provider of cloud-based communications and collaboration solutions for small business and enterprise companies
Sitecake - Drag and drop CMS for HTML websites. It's flat file CMS so it's pretty fast.
Dialpad - Switch is a cloud-based phone system built for Google Apps users.
Anchor CMS - Free and lightweight blogging system
Aircall - Aircall is a call center software of a new generation designed for fast growing companies. Setup instantly and integrates to your CRMs
Textpattern - Textpattern is an elegant content management system that is free, open source software.