Anyone ever used one of these and if so where do i find them. I would like a more accurate reading of my OG and FG
a glass hydrometer calibrated in distilled or even tap water at a calibrated temp is pretty damn accurate
search is your friend: http://www.homebrewtalk.com/f11/digital-hydrometers-34571/
Also, refractometers tend to be less expensive than digital hydrometers.