This may sound cheesy, but I really admire Amazon's website. We also run an ecommerce website, and we have gotten some great ideas from them. It is really a challenge for them to offer such a diverse spread of products and still allow such great navigation throughout the site.
I'll admit, their upselling is a little much at times, but it can be helpful I guess to some people. Their images are always there, their shopping cart always works, their searches are always functional. It is an amazing site.
I guess that's why they get the "big bucks" LOL.
Just my .02
-Elizabeth