Fandoms
You don't secure global releases and gross hundreds of millions of dollars without a few fans behind you. Aside from the many…many folks who plunked down their hard-earned cash for a ticket, Age of Ultron spoke directly to the horde of fans who follow the Marvel Cinematic Universe—both digitally and in analog form.
World Wide Wiki
What's Captain America's past with the Winter Soldier? Which movies feature Red Skull? In which film can we find the first appearance of Black Panther? Are these questions keeping you up at night, Shmooper? Or causing you to pull up Google every few minutes?
Well, wonder no more. The "Marvel Cinematic Universe Wiki" is here to help. This site is run by the fans, for the fans, and it doesn't just limit itself to movies. You'll find all the deets on Marvel television programming, comics—heck, even video games. You can also dig deep into obscure elements of the stories, like The Water of Sights where Thor has his Vision, er…vision. Check it out, but only if you have a few hours to spare. Bunny trailing is a real danger here (as are spoilers). (Source)
Cos's & Cons
Not satisfied with online interaction? Brave enough to venture out into public? Braver still to do so while wearing a cardboard suit of Iron Man armor? Then get yourself to a Comic Con—stat.
Comic conventions ("con's" for those in the know) are all the rage these days. The Comic-Con in San Diego remains the mack daddy of them all, but you can find them happening all over the world. Any place that has a convention center is a likely spot for these gatherings, which bring writers, directors, artists, and actors face to face with their fans.
Some of those fans are more, shall we say, enthusiastic than others. These are the ones that spend hours with a sewing machine and a hot glue gun, putting together a costume tribute to their favorite superhero. The hobby is called "cosplay," but some folks take it very seriously. In fact, a whole cottage industry has sprouted up, blanketing Instagram with superhero look-alikes striking dramatic poses.
The Avengers, of course, are a popular choice for cosplayers. Hey, who wouldn't want to bulk up like Hulk and paint themselves green? (Source)