The largest star known to man, possibly 2100 times the size of the sun. Man, just think about that for a moment. If you replaced the sun with VY Canis Majoris, the Earth would be INSIDE it, it's surface would reach Saturn and it would vaporize Pluto. That's freakin' HUGE.
...I don;t really know what I'm expecting people to contribute here; maybe I just want that to be the one interesting thing you learn today.