My Scientific American column this month praises the upside of techno-fear. Yes, fear of new machines is often irrational—but it also keeps us vigilant. When technology really does start to threaten the public good, public outrage frequently rights the ship.

Here are some of my favorite examples from the annals of consumer technology:

December 2009: Verizon's flip phones were programmed to take you to the Web when you pressed the “UP” button. An internal whistle-blower revealed that you got billed $2 each time, even if you immediately canceled.

Verizon's first response was to deny it. "Usage fees are not charged when a customer simply launches the Internet browser and lands on the Verizon Wireless Mobile Web home page, which is the default setting," it said in a statement at the time.

But the public was outraged, the Federal Communications Commission investigated, and Verizon turns out not to have been so innocent after all. It was charging $2 per accidental button-press—and it had to refund $52 million to customers and pay the FCC a record $25 million fine.

August 2010: The Lower Merion School District in Pennsylvania had issued MacBook laptops to every student. It had also installed software that permitted administrators to operate the laptop's built-in camera remotely and secretly. Although school administrators claimed that the software was intended to help track down laptops after they'd been stolen, an investigation determined that the district had taken over 30,000 pictures of students (including at home) and 27,000 screen shots of what they were doing.

After a public outcry the school system wound up paying $610,000 in fees and fines. It immediately ended the spying program and implemented new policies to "safeguard the protection of privacy" of its students.

September 2011: Google's Street View vans have been driving and photographing roads and their surroundings around the world since May 2007 so that you can see what any address looks like on Google Maps.

Unfortunately, those cameras also capture people—who are occasionally doing things they would probably rather keep private, such as leaving strip clips, hiring prostitutes and so on.

When public outrage (and fines in several countries) erupted, Google added tools for blurring faces and license plates, and for flagging images for removal.

January 2012: Protests, petitions and demonstrations ignited when a front-page New York Times article documented working conditions at Foxconn Technology, the Chinese factory that builds Apple's products. The article mentioned fatal accidents, employees working with toxic chemicals, long hours, low wages and suicides. (Apple was singled out but Foxconn also builds products for Sony, Panasonic, Samsung, Sharp, Asus, HP, Dell, Intel, IBM, Lenovo, Microsoft, Motorola, NETGEAR, Nintendo, Nokia and Vizio—products that include the Xbox, PlayStation and Amazon Kindle.)

The outrage set in motion a long series of reforms that continues to this day. Apple hired the Fair Labor Association (FLA) to survey 35,000 Foxconn employees about factory conditions. Foxconn raised salaries as much as 25 percent.

A year later the FLA reported that Foxconn had made "steady progress," constructing additional restrooms and limiting overtime hours to 36 a month and three a day. Apple’s own Foxconn workers' average workweek dropped to 53 hours.

Most interestingly of all, the scandal triggered a new emphasis on exploring tech manufacturing here in the U.S. Apple's new top-of-the-line Mac Pro, for example, is built in Austin, Texas.

In short, you shouldn't assume you can get away with anything in our connected age. The public will find out—and the outrage will hurt.