What?
Sawyer serves the reference needs for all Div 1 and Div 2 students, so they have a massive collection of books and very smart bookcases to support storing and displaying a selection of loanable books. These bookcases are fitted with wheels that move along tracks on the floor. When users turn the handle to the side of each bookcase, the case would move towards the direction of the turning movement.
Why is it great?
The design works on a single valuable observation: that the aisles on either sides of each bookcase are not occupied all the time. This means that if we can eliminate these often un-used space, we could reclaim a lot of storage affordance for the bookcases.
The handles on the side of each bookcase has a circular design that informs users to use a turn motion on them, so they serve as effective signifiers. It is however not clear that the green pin helps lock the bookcase in place - a potential design shortfall.
Finally, the bookcases provide instant feedback (moving left/right) when the handle is turned, and the direction of handle turning maps intuitively to the direction of the bookcase movement.