If you can forego waterproofing, Checktemp F from Hanna Instruments is a great thermometer. It's accurate to 0.1 degree F and comes with a handy little calbration slip to tell you if it has a bias. It isn't waterproof, though.
The splash-proof will have to suffice because I haven't found any truly waterproof. Looks like the ThermoWorks thermapen also comes in every color under the sun. Attractive dual use idea for the grill too SwampWater! I appreciate and respect the honest and accurate advice that I get from the smart brewers here. Cheers!
A bit of price shock at first though. Took me awhile to decide if I really needed it. Turns out I did. My candy thermometer that I put in my mash was 6 F too high. I was mashing too low.