According to the National Institute of Standards and Technology (NIST), the smallest microwave oven is a creation of researchers at NIST and George Mason University. The device was developed for use in lab-on-a-chip applications to analyze micro liter samples.
Mail Online reports claim that the smallest microwave oven was one developed by Heinz in 2009. The device called Beanzawave, which is 7.4 inches in height, 6.2 inches wide and 5.9 inches deep, is powered through a USB cable plugged into a laptop. The mini microwave is capable of heating or cooking small quantities of food, making it ideal for desk-bound workers and students.