Here's a gee whiz presentation of the size of our universe and a review of how science's idea of the universe has changed over time.
The size of the universe is normally given as 13.7 billion light years. But he points out that the Hubble space telescope is taking pictures of galaxies that are 46 billion light years away from earth, making the "observable universe" 92 billion light years across. This video claims that current theory says that the "whole universe" is 10^24 times bigger than the observable universe. It then give you a sense of scale by saying that the whole universe if bigger than the observable universe as the size of the observable universe is to the size of an atom. Wow! Now that's big!