If you're reading this blog on your laptop, I hope your using protection. No, not that kind of protection, just something to protect your lap from the heat generated by the underside of your computer. According to the journal Pediatrics, laptops can heat up to a high enough temperature to cause a nasty rash, especially if you have it against your bare skin for hours at a time, basically cooking your flesh.
It's very easy to guard against this, (after all prevention is better than a cure) use a flat cushion, or if you're like me, buy a laptop stand from Ikea, it's very comfy and gives your computer a nice even surface to sit on. (And no, I'm not on commission.)