My wife has a Macbook Air and I use a Macbook Pro. Our power cables for our respective computers are plugged into the same power strip under a desk, and the magnetic part of the power plugs is visible coming out of a hole in the top of the desk but the problem is that both plugs look identical and both plugs fit each of our computers. I wanted to know if it's "OK" to use her Macbook Air power cable (45W) to charge my Macbook Pro, and if it's "OK" to use my Macbook Pro power cable (85W) to charge her Macbook Air? When I say "OK" my main concern is that there is no inherent fire danger by swapping the power cables. I assume of course that the 45W power cable that came with her Macbook air would charge my Macbook Pro much more slowly than the 85W cable, but will the 45W power cable charge the Macbook Pro if I leave it connected overnight? MY MOST IMPORTANT PART OF THIS QUESTIONS IS - is there any fire danger by freely using each others cables? Any advice would be greatly appreciated... Thanks!