It's amazing to see just how far computers have come in my lifetime. When I was a kid, our computer was that thing that sat in my dad's office, that we were only rarely able to touch. These days, I always have a computer (or two) with me, and three different rooms in my house have dedicated PCs. And now there are complete computers you can buy for less than a meal. And now there's a new competitor in the sub-$20 computer market.