Best thing about a boot dryer? Starting a sub-zero temperature day by pulling on warm boots. So I got this idea: Heat my hiking boots this morning in the microwave oven! For just 60 seconds, on half-power. These boots have no metal components, so they could not possibly burst into flame or melt down.
Based on this one-time experiment, however, my advice is DO NOT DO THIS!
(Wool gloves and socks are okay, though. Except for the odor.)