We've seen some pretty amazing Lego creations over the years, and this has to be one of our favorites. (Or at least, one of today's favorites.) A YouTuber named "horseattack" has assembled a Lego printer that uses little more than a felt tip pen to greet us all with a hearty "Hello World" (although we're sure it can write other stuff as well). And no sir, this isn't a Mindstorm kit... the design, coding, and construction are all from scratch. See for yourself after the break.