Openbravo is the leading fully functional integrated web- based open source ERP. If you are looking for a system to manage your business... It's time to get your own ERP!

Alfresco offers a flexible, scalable content management platform that combines open source advantages with a powerful, enterprise-class engine

vTiger is an open source solution for marketing automation, sales force automation, order management, inventory, quotes, estimates, invoicing, FAQ, trouble tickets, RSS, webmail, etc.