This document compares several open source ERP systems based on evaluation criteria like popularity, costs, customization, functionality, and user experience. It provides pricing information for open source ERP products like Openbravo, Compiere, XTuple, and OpenERP. Several comparison tables are included that analyze and compare the different systems based on various attributes. The findings suggest that OpenERP is a good choice in terms of risk and integration costs, while Openbravo is best for SAAS-based applications and Compiere offers both ERP and CRM solutions.