Farewell, flying future Is it a bird? Is it a plane? No, it's a world that's way more pedestrian than we ever expected. NOTE FOR 2020 READERS: This is the 14th in an award-winning series of open letters to the next century, now just one generation away. Babies born in more than 40 countries this year are expected to live to 2100 and beyond. These letters examine what the world could look like then — and how we can make the best scenario happen. Dear 22nd Century, Hopefully there is some kind of statute of limitations on inappropriate thoughts that flitted through the heads of those of us who were alive on September 11, 2001. (You know about 9/11, right? If not, you