Coming up to lunch time, at work my PC froze. No mouse response, no keyboard response, not even to Ctrl-Alt-Del. So I powered it off, left it for 10 seconds, then powered it up again. No picture. Just the sound of a fan. Actually that fan is rather load. Hmm, that fan is VERY loud. Is this thing going to take off? Should we take cover? I powered it off again and had lunch. After half an hour it was back to normal. And after another half an hour it went through the whole performance again. IT support came and had a look at it. They put the diagnostic CD in. It got to the step where it said "setting processor fan to high speed" ... and hung. A Dell engineer will be in tomorrow to give me a new motherboard and fan.
I came home. I put the oven on. There were a couple of brown-outs while it was heating, which did my faith in electrical appliances no good at all.
I put the TV on, thinking I might catch a Doctor Who trailer as it was just before 7. (I wondered how sad it was to put the TV on in case there might be a trailer, but decided in this case, not sad at all). My hypothesis proved correct, but towards the end of the trailer, the picture faltered, became black-and-white, and very snowy. As did BBC2. And after a few seconds it was all back to normal. So I think that provides useful corroborating evidence against the TV as the device at fault there, as it was just receiving the plain old analogue signal. This raises the possibility, if the deterioration is rapid, that I may be able to record Doctor Who on Saturday, but not to watch it. This scenario reminds me of The Likely Lads trying to avoid hearing the outcome of "the match". (Were there any other episodes of that? It always seems to be the same one when I have the misfortune to catch a repeat).
I finally summoned up the courage to turn my PC on here at home. So far it hasn't broken.