e-Commerce module for Drupal. Simply the biggest module for Drupal. Bigger than Drupal itself.
* Shopping cart and product 'look and feel' are themeable
* Create taxes, charges and discounts
* Subscriptions and recurring payments
* Receive donations
* Sell file downloads, shippable items, bundles or even customizable products
* Inventory management
* Payment and shipping plugins: The system can use PayPal, Authorize.net, e-xact, C.O.D or you can roll your own.
* Invoice generation and email notifications
* Transaction and payment workflows
* Reports and sales summaries
* Customers can review their order history
* Run an auction site