Jennifer Saranow notes that “the falling cost of microcontroller chips and the lure of easy online sales” are leading to Revenge by Gadget:
A Tennessee company has created a $50 device that shuts up other people’s dogs by answering their barks with an ultrasonic squeal that humans can’t hear. (The unit is disguised as a birdhouse.) British inventors are exporting a new product for people who hate lousy drivers — it’s a luminescent screen that fits in a car’s rear window and, at the driver’s command, flashes any one of five messages to other motorists. These include a smiley face, a sad face and phrases like “Back Off” and “Idiot.” (Since the product’s U.S. debut, the company says it also has received several requests for images of offensive hand gestures.)While many of these gadgets are built by small companies or basement tinkerers, the field has caught the attention of graduate students at MIT’s Media Lab, where it is known as “annoyancetech.” Among their recent creations: a “No-Contact Jacket” that, when activated with a controller, delivers a blast of electricity to anyone who touches the person wearing it. During a demonstration in Japan, co-creator Adam Whiton says it drew interest from women who were eager to retaliate against gropers on the subway.