Our view of the immediate Solar Neighborhood has changed dramatically in the past decade with the discovery of an ever-growing population of cool, dim brown dwarfs.  These objects, incapable of sustained hydrogen fusion, are intrinsically long-lived, time-variable objects, making them potential probes of (sub)stellar star formation history and Galactic chemical evolution.  Our understanding of cool atmospheric physics and brown dwarf evolution has been fed with the nearly 1000 L and T dwarfs identified predominantly with wide-field near-infrared imaging surveys such as 2MASS, DENIS and SDSS.  However, it is the even colder Y dwarfs, recently uncovered with Spitzer & WISE, that may provide our best opportunity to exploit brown dwarfs for Galactic science.  In this talk, I motivate the search for the coldest brown dwarfs, describe their discovery and summarize results from early spectral reconnaissance, focusing in particular on the role the FIRE spectrograph has played.  I will also describe how the planetary-like atmospheres of these objects can be used to calibrate future direct detection detection experiments of Jovian exoplanets in habitable zones.