Researchers have long waffled over whether mobile phones cause cancer. The concern persists since more than 90 percent of people use them, according to a University of Sydney study (PDF) published this week in the journal Cancer Epidemiology. After examining 29 years of mobile phone use in Australia, the research team “found no increase in …

Now playing: Watch this: UL fights hoverboard fires with new safety standards 1:53 Let’s just start out by saying that today’s “hoverboards” can’t actually fly or hover. What passes for a hoverboard, a device teased at more than 30 years ago in the “Back to the Future” movies, is actually a self-balancing scooter. Besides being earthbound, today’s hoverboards have another …