Laptop is a mini computer that you can use on top of your lap.
But you aren't recommend to do so.
The heat from below part of the laptop would slowly burned your upper skin and would result red marks.
Anyway... I guess that rule was meant for any kind of device...
Last night, after I had done some preparations for today's meeting, I played a game on TABOO (my tab).
I was lying down and held it on my chest.
Minutes later, I started to felt ache on my chest...it's aching and I can't breathe...
"Is this a sign of heart attack?"
I soon realize that the ache might caused because of keeping TABOO on my chest.
I quickly put it down, but the ache didn't go away.
I spray a kind of warm oil ("minyak angin" in Indonesian), it felt a bit better, but still aching.
I can't sleep for about half of hours, thinking that I would die because of keeping a hot tab on my chest...
The ache disappeared in the morning, though I still feel hardly to do deep breath.
People, don't ever tried it.