This is following the post I had done earlier on the skipping of payment page. I decided to put in the actual context of the problem and the solution to it..

1. The seller wants to give away samples to his customers.
2. He may or may not charge the customer for shipping. This actually depends on the customer’s choice of shipping options.
3. Let us assume that the free shipping is available ( since free sample itself is available and the seller is keen in promoting the product )

Under such circumstances, it is ideal to skip the payment page altogether. However, since it a promotion it may still require a billing address for accounting purposes.

We must also consider that all shopping cart systems require a payment method to be selected so we can work around that using a dummy payment option which is assigned by default..

You can check out the demo here. It works well for Oscommerce, Zen Cart, CRE Loaded and Osc max. The same mod can be developed for other cart systems too ( just let us know ).

Please write back if you think it was useful. Feel free to write at us support@e-cart-solutions in case, you need a similar mod or a modified/advanced one.

Cheers
Shiva