The Squat Lobster, Gastroptychus spinifer, has a body that is about 1/2-inch wide and 1-inch long. Its eyes are quite large for such a small animal, and may be capable of seeing in the UV range of the elctro-magnetic spectrum.
Image courtesy of Bioluminescence Team 2009, NOAA-OER
(via: Live Science)
(ಠ_ಠ)
Oh god. Look at that thing.