Unfortunately, my computer crashed the day before yesterday for no apparent reason. Maybe the fact that it's almost six years old had something to do with it? Fortunately, I married someone who is much more computer savvy than I am and he was able to fix it (by reinstalling Windows) without losing any of my data.
It is a scary moment when you can't get your computer to turn on, even in safe mode. It is a scarier moment when your husband has your computer case opened up on the floor and is pulling out handfuls of wires and circuit boards. I hadn't backed my data up since November. He had to pull out my hard drive and hook it up to his computer before he could copy my computer's data onto our external hard drive. Lesson learned. I need to back up more frequently.
How often do you back up? If you don't have an external hard drive, I highly recommend you get one. It makes backing up so much easier, and in the case of an emergency, you can just grab the hard drive and run out of the house, which you can't really do if you have a desktop computer.
Another recommendation about computers: I think it is wise when shopping for a computer to buy the absolute best one you can afford even if it is overkill for your current needs. That way as technology improves, you can grow into your computer instead of needing to upgrade. Had I bought a basic computer six years ago, I would have already had to replace it. I expect to get another year or two of life out of this one (I did install more memory last fall) which is much longer than most people keep their computers.
This is also a good strategy because it reduces cyber waste, which is a significant environmental problem. PBS aired a great Frontline special about this several months ago. If you're interested in the topic, you can find it online here.