The summer movie season officially kicks off in grand fashion when "Marvel's The Avengers" opens in over 4,000 theaters this weekend. With a cast that assembles Hollywood heavyweights to play some of the most beloved superheroes from the Marvel comic book universe, the movie is as close as you get to a sure thing at the box office. Since opening No. 1 in all 39 international markets it debuted in last weekend, the action-packed blockbuster has already amassed over $260 million abroad. When domestic ticket sales are added to the equation, many experts predict the superhero supergroup will pass the billion dollar mark with cape-flying colors. We all know "The Avengers" is going to make gobs of loot, and by most critical accounts it deserves to, but here are five fun facts you may not know about the film.