A Journey, Seoul by Mimi Son and Elliot Woods.
Seoul is a piece of interactive art that consists of numerous clear acrylic plates with white detailing added to them. The plates can be placed into a box by the viewer that illuminates the plates and projects colors and patterns onto them. The project focuses on the viewer's memories, calling to viewer to assemble a box that means something to them.
I like how self-defined the piece is. It tries not to be meaningful to the viewer by making a statement on its own. Instead, its meaning comes from the meaning that the viewer puts into it. This is interactive art on a very base level, i.e., the user has a hand in creating their own version of the piece. In fact, no two viewers will view the same piece. While they both might assemble the same plates in the same order, nobody will assemble the box for the same reason, thus fundamentally changing the piece.
A Journey, Seoul is part of a series created by the artists that includes a couple of other cities. Each city provides different interactions-- for example, A Journey, London, uses changing sounds and lights to tell different stories through the same physical model. Each iteration of the project includes the user more and more in the personalization (A Journey, Dublin is the last in the series and allows the viewer to actually draw on the panels to create their own narrative completely).
Of the series, though, I think Seoul is the strongest. London leaves little up to the viewer, making its interaction a mostly passive experience. Dublin, while quite visually pleasing, seems to give too much freedom to the viewer. The piece becomes more of a white-board than an art piece. Seoul, on the other hand, gives the viewer enough freedom to make their own memories from the predefined plates, while still keeping control over what the viewer is seeing to a certain extent. There is value to limiting what a viewer can do, as it forces the imagination to fill in gaps in their head, rather than giving the viewer the freedom to fill in those gaps in the physical world.