If you’re in San Diego this week, don’t be alarmed if you see large numbers of Iron Mans, Captain Americas, Ninja Turtles, Superwomans, Storm Troopers and Batmans roaming the streets. Comic book fans are converging on the San Diego Convention Center for the annual Comic-Con Conference that begins Thursday. The conference, which is expected to draw nearly 150,000 attendees, encourages die-hard comic book aficionados to dress up and act like their favorite characters. Most people have a favorite superhero and have seen at least one comic book-inspired movie…but who is the most valuable superhero of all time?

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The Daily Ticker posed that question to Steve Weintraub, editor-in-chief of Collider.com, a site that reports about and provides commentary on movies, entertainment, gadgets and video games. A self-described comic book devotee, Weintraub was unflinching in his response: Superman. Detective Comics Inc. introduced the world to the character and cultural icon in 1938 when it published Action Comics No. 1, considered to be the "holy grail" of comic books (Action Comics No. 1 has sold for millions of dollars in private auctions). Superman creators Jerry Siegel and Joe Shuster probably never imagined that their superhero who is "faster than a speeding bullet and more powerful than a locomotive" would be one of the most recognizable and bankable comic book stars 75 years after his public debut.

(Watch the video above to see who Weintraub ranks as the second-highest grossing superhero.)

Weintraub brings up an important point when determining a superhero’s worth: movie ticket sales and comic book sales are just one small part of what makes a character so profitable. When the first Star Wars movie hit theaters in 1977, Star Wars director, writer and mastermind George Lucas literally spawned another empire: one that was worth billions of dollars in merchandise and licensing deals. That’s why media giant Walt Disney (DIS), bought Lucasfilm for $4 billion last October, cementing its frontrunner status in the comic book universe (the company paid $3.96 billion in August 2009 to acquire Marvel Comics – the comic book powerhouse behind some of today’s most memorable heroes: Spider-Man, Iron Man, Thor, Captain America and the Hulk). Disney CEO Bob Iger says the company will “aggressively” expand the Star Wars franchise and will release Episode VII in 2015.

Comic book fans have a lot to look forward to in the next few weeks, months and years: “The Wolverine” (July 26); “Riddick” (Sept. 6); “Thor: The Dark World” (November 2013); “300: Rise of an Empire” (March 2014); “The Amazing Spider-Man 2” (May 2014); “Teenage Mutant Ninja Turtles” (June 2014). The thousands gathering at Comic-Con will attend private screenings of these films but also get the opportunity to meet the stars that bring these characters to life.