Quill.com sells a huge selection office supplies— from dozen varieties of ink cartridges to paper products. Shoppers who are browsing multiple product pages might have a hard time keeping track. This is why quill.com has a prominent floating element (anchored to bottom of page) that displays recently viewed items.
What I like about this tactic—
1: Makes recently viewed items super accessible. Shoppers can browse around freely knowing their shortlisted items are just a few pixels away. Eliminates the need to use shopping cart as temporary holding spot.
2: Minimalistic design that nicely blends into existing site design. This frees vital screen real-estate for marketing more products.