When viewing one of Freitag's unique items, this recommender suggests other items with similar colors. The system first identifies the top 3 colors of every item based on the corresponding photo (one of them will be the white background). Then, when an item is selected, the backend filters other items based on the selected item's primary and secondary colors.
Login: "freitag" / "freitag-DEMO"
About 3 person days
The bulk of the effort would be to integrate these product recommendations into the Freitag webshop.