One day 24-year-old Kristin Manigault noticed the skin on her legs had become irritated.
"It started looking really funny. Then I kind of overlooked it," Manigault said. "It started to spread, and of course that made me really nervous."
When she went to the doctors, they gave her a shock: She was diagnosed with erythema ab igne, otherwise known as toasted skin syndrome. The reputed culprit? Her laptop.
Manigault uses her laptop as many as seven hours a day -- enough to apparently cause the rare condition.
"It can get pretty hot," she said. "It would hurt once the laptop got really hot, and I sat it there and it kind of got really tingly."
Before central heating was common, people suffered similar effects from sitting too close to the fireplace. But now technology has brought toasted leg syndrome back. In a recent case, a 12-year-old boy who used his laptop to play games became the 10th reported case in the past six years.
"There are some reports of skin cancer developing within this eruption, although that is far from the rule," Eastern Virginia Medical School's Kimberly Salkey told "Good Morning America."
When laptops work hard, the processor creates a lot of heat. If the fans and vents are baffled by your legs, temperatures can soar -- up to 117 degrees, according to a infrared thermometer used in a "GMA" experiment. According to Salkey, some can run up to a scorching 125 degrees.
Sometimes, the computer doesn't feel as if it's burning the user, but acts more like a sunburn -- damaging skin over time and without warning. According to experts, the obvious advice is to pay attention to how hot your computer gets. Rather than putting something like a pillow between your legs and the laptop, which can muffle the fans, putting the laptop on a desk or hard surface can help get air through the cooling fans.
Computer laptop desks can offer a comfortable solution with a pillow on one end and a laminated surface on the other to place the laptop on.