Have found conflicting answers on the internet in regards to this. So I must ask, is it safe to carry to my MBP (vertically, obviously) in a backpack while it's in sleep mode, or would it be preferable to turn it off when transporting it? Don't really have the money to invest in a special laptop carrying case or anything similar for the time being... The reason I'm asking this is because I just had my HDD replaced after owning my MBP for only a year and a half. Call me paranoid, but I've developed this thought that carrying my laptop in my backpack all the time may have jarred the HDD, leading to this replacement. Any advice would be greatly appreciated.