customize shopping cart I'm just looking for a module in drupal to make a shopping cart customizable. I mean that there will be no products, I just need that people put the amount of money they need to pay and just click proceed to checkout and goes directly to the payment gateway with the amount written. I've been looking to Commerce and Ubercart but I couldn't figure out if there is this option.
Can you help?
It looks like you need Donation functionality, may entitled as something else. 

Following modules might help you.


https://www.drupal.org/project/commerce_donate
https://www.drupal.org/project/paypal_donations
https://www.drupal.org/project/donate


Or a custom form which interacts with https://www.drupal.org/project/pay