According to Myhrvold, modernist cooks need to stock up on a good thermometer as well as two types of scales. This Sper Scientific Thermocouple Probe Thermometer ($82) is particularly useful in monitoring the temperature of food cooked sous vide. Rather than using measuring cups, opt for this Escali Digital Multifunctional Food Scale ($40). Some molecular recipes, however, call for even more minute measurements of thickening or coagulating agents like agar-agar and sodium citrate, which cannot be measured on an Escali scale. The American Weigh Signature Series Digital Pocket Scale ($30) weighs up to 100 grams in 0.01 gram increments. We're talking granules here.
Scales and Thermometers