Dolibarr

Dolibarr ERP & CRM is a modern and easy to use web software to manage your business (contacts, invoices, orders, products, stocks, agenda, emailings, etc...). It's an opensource and free software designed for small companies, foundations and freelances. You can install and use it as a standalone application, or online on a mutualized or dedicated server to use it from anywhere. Dolibarr is also available on ready to use Cloud services.

 Source:http://www.dolibarr.org/