I have noticed that a lot of web sites that contains product category pages give the user an option to toggle between a list view and a table view of their products. Usually the only difference between the views is how the product image is placed relative to the product info. The toggle-buttons is usually grouped together in the upper right corner, above the products. I've seen this on YouTube and various other sites.
I have myself never used them or tested if a visitor really clicks on them. I think that they are usually a redundant feature. Is this the case?