A long time ago I used to type everything I wrote on my computer. Then one day, half the files in my "unfinished" folder got corrupted and I lost a bunch of stories I'd been working on. I was heartbroken. I tried to re-write them, but they just weren't the same. From that point on, I started writing everything out by hand, so I'll always have a hard copy.
And I've found I like hand writing so much better. While I type fast, my accuracy is horrible, so with writing I don't end up stopping every other word to fix typos. I can just go with the flow of my pencil. The other advantage is that nobody but me can read my handwriting, so if I'm writing during my downtime at work and get that eerie feeling that people are lurking behind my desk, I'm assured that there's little chance they can read what's in my notebook.