It's actually quite good when this sort of thing happens, provided you don't lose data. When you get your machine repaired, it is a brilliant excuse to have it upgraded as well. Thus, I now have a hard drive that is twice as big, has twice the memory and has an external drive to back up large video files in the future.
The greatest loss, had I not taken precautions, would have been the Thinking Maths DVD project, footage of a trainer doing around a dozen demo lessons, edited and voiced over by a fellow secondee and myself. We learned a great deal about film-making in a very short time. Rapid pans and zooms make audiences feel sick. Some children feel obliged to wave whenever they see a camera.
Children whose parents haven't filled in the permission form have to be placed strategically out of shot. These are all important considerations, but they are insignificant compared to the golden rule of teacher training videos.
Rule 1 is to make sure you have a full class of children in view at some point. This is to make it easier for the viewers who want to count the pupils. The quicker they realise that they are not seeing the same six kids over and over again, and are in fact watching a standard 30-odd, the better.
These people, and I have it on good authority that they exist, can then get on with watching the film rather than saying: "That's all very well, but I've got five times as many weans as that in my room."
There is a scene in one of the lessons that I particularly like. The pupils have been asked about the different ways of getting a rectangle of area 12.
We have 4 x 3, 6 x 2, 12 x 1. Suddenly a boy realises that you can get 12 by multiplying 24 by a half. Or 48 by a quarter, and so forth. "I didnae know ye could dae that!" says his pal. "That is so cool!"
Copyright reasons prevented us from doing so, but it would have been good to back this with Fun, Fun, Fun by the Beach Boys. Contrast with Pink Floyd's Another Brick in the Wall, appropriate to the few times when I taught maths.
Gregor Steele's MP3 collection is safely backed up.