You can convince your customers to buy more products even on checkout.

This module displays products related to cart's products. If there aren't any products in cart or all of the products in the cart haven't related products, this module will be hidden.

DEMO (in the demo site, this module is placed on checkout, but you can place it anywhere):

http://colors.womgoo.com/

ADMIN:
http://colors.womgoo.com/admin
user: demo
pass: demo

No files or data will be overridden.