This LEGO creation doesn't just give us plastic brick versions of Chell, Wheatley, and the Space Core; it also captures Portal 2's final confrontation—all while keeping your books in place. Portal 2 spoilers within.
Builder Lego Junkie came up with this playful scene, which shows Chell hanging onto Wheatley's head (which is attached to GLaDOS' body) after traveling through a portal to the moon. Space Core is just along for the ride, enjoying the fulfillment of its lifelong ambition. Spaaaaaaaace.
Lego Junkie says that there is no photo manipulation involved; Chell really is hanging on upside down by a single peg. You can see more views of the bookends on Flickr.