But if you would like to archive your blog, that is, back it up onto your computer, here is how to do it with Google Blogger
Remember that when you write a blog, it's stored on Google's server, not your computer. I don't expect anything to go wrong there, but if it does, you will lose your blog. As I have been ranting about for years, best practice is to back up your files. It's your responsibility.
Update October 31, 2001. Back up has now moved to Settings > Other. Look for settings along the left-hand side of your "My Blogs" page, under Overview, Posts, Pages, Comments, etc.
Why it's hidden like this, I have no idea.