One of my favorite collections in this context is hairpins. The way the pins are displayed together with the packaging material moves me. Often, the images illustrate how to use the product or showcase its style (though they are frequently gender-stereotyped). The presentation is neat, systematic, and clearly structured, making it immediately apparent what the product is for and how it can be used.
Another example is chocolate packaging, where additional values and premium qualities are conveyed through design. The packaging itself is so refined that no extra gift wrap is needed. The chocolate bar is divided in an unusual way, allowing pieces of various sizes to be broken off. Again, showing how the product's function directly influences its design.
Or take the sachets of chewing tobacco from India, which are connected in a long row. When hung as a strip, they serve as a display and yet can easily be torn off individually. Here too, the packaging plays a key role in both product presentation and usability.