OpenERP is a complete ERP and CRM. The main features are accounting
(analytic and financial), stock management, sales and purchases
management, tasks automation, marketing campaigns, help desk,
POS, etc. Technical features include a distributed server, flexible
workflows, an object database, a dynamic GUI, customizable reports, and
SOAP and XML-RPC interfaces.

Before you can use openerp-server, you will have to set up
postgresql. All you have to do is issue the following command:
  createuser -U postgres --no-adduser terp

This will setup OpenERP for the use with postgresql on localhost.
There is no need to set a password on localhost. However, if you are
going to run postgresql on a different server, you will have to run
createuser like this:
  createuser -U postgres --no-adduser -P terp