You never know what are going to find at the convention center each year, but if you look close enough you will find the products that started all this madness more than 40 years ago.
You can still find comic books at Comic-Con, but the movie world has really taken over.
"Tron: Legacy," the long-awaited follow-up to "Tron," has already gotten rave reviews from fans treated to eight minutes of the December release.
"Comic-Con really is responsible for making this movie possible," said actor Jeff Bridges. "Three years ago we showed only two minutes of a scene we shot and it got a wonderful reaction. That caused Disney to say, 'We will finance that.'"
"I think there is so much anticipation, so much affection for this story and the first film," said actor Michael Sheen. "I think the audience is just going to go crazy."
Hollywood goes all out for the annual San Diego affair. Among the films gunning for publicity is "Drive Angry" with Nicolas Cage in the driver's seat.
"These people love their movies with a bit of adrenaline to them, and so do I," said Cage. "I think 'Drive Angry' is a good match for Comic-Con."
There are many movies at the annual event that are hoping for buzz to help create blockbusters: "Scott Pilgrim vs. the World," "The Other Guys" with Will Ferrell and Mark Wahlberg and "The Expendables,"which brought Sylvester Stallone to Comic-Con for the first time.
"This is the new audience," said Stallone. "This is how people make or break films. This may be a novelty to these people because they haven't seen this sort of action film, you know, most of them are so young."
By Sunday, an estimated 125,000 people will visit Comic-Con before it's all over for another year.