The Fermi National Accelerator Lab near Chicago has a new toy: the Holometer. As its rather fancy name suggests, the Holometer is for testing whether our universe is actually a 2D hologram that's painted on some kind of cosmological horizon, popping into 3D whenever we attempt to observe it (i.e. always). The Holometer will gather data for the next year or so -- after which, there's a very good chance that it'll be able to tell us whether the universe is a hologram or not. And, of course, if the universe is a 2D hologram... what does that make us?