Dekbedovertrekshop is another Drupal/Ubercart based niche shop. They sell all sorts of bed linen (dekbedovertrekken) in all sizes.
There are a lot of tweaks and small customizations regarding the cart display, checkout handling and smart "back" functions based on Drupal hooks, theme overrides and jQuery.
The catalog pages and their filter forms are Views.
The SEO advantages of Drupal are fenomenal, the project is a few weeks old now and we see te visitors come in at increasing numbers every day. This really gets this shop ahead of the competitions (at least for now...)