One Space Or Two?

So, a little while ago, my friend Val, soon to be Mrs. Steven Q. Pullen, wrote a little bit about how she was corrected by a friend because she put two spaces after a period at the end of a sentence. The friend said that she was taught to put only one space. They looked it up, and apparently it was once taught to be correct form to type two spaces after a period (which is how I was taught, and I cannot be moved on this practice) because when typewriters were the main form of text production, all letters took up the same amount of space on the paper. So, now, we have computers that even out the font sizes per-letter, and so it is being taught that only one space is necessary to separate sentences. And apparently, some pieces of "software" will automatically correct this "mistake" of two spaces. Val is a two-spacer. Steve is a two-spacer. I am a two spacer. What is your stance on sentence-concluding spacing?? Here is what I wrote to Val:

I will put two spaces between sentences until I'm dead...and I'll tell you why:
People who use one space between sentences are the same people who kick puppies. They're the same people who laugh when a little girl wearing a bonnet drops her ice cream cone goodness-side down onto an ant pile. They laugh at the girl; they laugh at the bonnet; they laugh at the ants. For that, I will never forgive the one spacers, or their one-spacing computers. The one-spacers have allowed the computers to take what is correct, and automatically make it incorrect. And one day, when one little "correct error" turns into robots taking over the world...well, then I knew it!! One-spacers, your life is moving too fast. Take time to stop and appreciate an extra space, give your battered puppies some kibble, and buy the little bonnet girl another scoop of Rocky Road. And next time you're typing, and habit tells you to continue being a single-spacer, just think...would you rather fight the wretched habit of single-spacing your sentences, or would you rather fight the robots?
As for me and my house, we will double-space after sentence-concluding punctuation.