This is the $25 Star Wars Death Star Coaster Set available from ThinkGeek. Individually, each of the nine glass coasters contains a cross-section of the Death Star. When stacked, they create a 3D image of the superweapon. When broken, they create a roommate who'll bitch at you for breaking his Death Star coasters. Calm down, Derek, it's not like I did it on purpose (I totally did it on purpose, I also hid a handful of pieces of the Millennium Falcon LEGO set he's about to build). "You're evil." I'm who the devil prays he was.
Keep going for a couple more shots, including one of each individual coaster.
Thanks to carey, who I could tell was just admiring my oversized drink coasters. "Those are empty pizza boxes." Nature's coasters.