This Magento Commerce extension allows the site owner to create any custom shipping option that would show up in the "Shipping Method" portion of the one-page checkout. Currently the extension is preset to create a very common shipping method called "Use My Own Shipping Account" option. When the customer selects this option it will display 2 drop down selector boxes (select company and shipping service) and 2 text fields (all fully customizable by site owner). Also this extension gives you the ability to charge a surcharge for this shipping option based on number of products or just per order. You can customize the shipping name and create/edit any shipping fields.