This morning, my laptop was subjected to some unscheduled gravitational and percussive stresses. Fortunately the hard disk and the screen, favourite points of failure in laptops I've dropped in the past, survived the incident -- but the mousepad stopped working. I was getting a mouse pointer, and the mousepad device appeared to be there when I asked the machine what hardware it thought it had, but I couldn't persuade the pointer to move around when I wanted it to, and clicking on buttons resulted in no perceptible effect at all.
So I hunted around for a teeny-tiny screwdriver, and I dismantled the laptop, waggled various likely-looking cable connectors, and reassembled it. Then I muttered darkly under my breath, went and found the replacement DVD drive, and repeated the exercise -- substituting the new one for the old before reassembly.
Now my mousepad works, and I can burn CDs once more. I'm assuming I can write to DVDs as well, but I haven't attempted to do so because I don't have any blanks to hand.