After going through several analog and digital thermometers I stumbled across one last night at the kitchen gadget store that actually had a digital commercial grade one with a calibrating screw that is water-proof. Wow....my trusty analog that I thought was dead on is apparently off by 5 degrees. No wonder my brews haven't been hitting their FGs. For 20 bucks this thing came with directions on how to callibrate and gave a precise temp within 8 sec. I'm sold.... It's the 9842 model.
I got this off Amazon and like it a lot. It was not calibrated properly when it arrived, but that is remedied now. It is indeed waterproof, as I dropped it in my mash. I had the other taylor digital instant read (non-waterproof, no calibration) and it was pretty terrible for the homebrewer's needs.