Warren is the founder of the cultural phenomenon of an art project called PostSecret. The project invites individuals across the world to make their own postcards with secrets scrolled on them.

These secrets have traveled in art exhibits nationwide and also can be seen at www.postsecret.com. In the course of a week, Warren receives about 1,000 postcards.

Warren’s fourth book of secrets, “A Lifetime of Secrets,” was released today, and he said this book takes a different approach than the others.

“In (‘Lifetime’) I have hundreds of never-before-seen secrets from people as young as 8 and as old as 80 sharing their funny, sexual, shocking secrets in loose chronological order,” he said. “They really trace the story of all of our lives. There are surprising ways our secrets change through different stages of our lives and there are interesting ways in which our secrets stay exactly the same.”

Since November 2004, Warren has collected secrets from across the world in multiple languages.

“I had a very boring job, so I think boring work can really motivate you to pursue interesting projects,” Warren said.

Warren himself has no training as an artist.

“I think of myself as an accidental artist,” he said. “It fell upon me. There’s an artist inside of all of us, more important than talent and training if we could just find the courage to appear vulnerable. Our work would be very meaningful.”

Since Warren receives so many postcards each week, not all of them make it onto the site. Each Sunday, the Web site is updated with secrets Warren hand picks.

“I pick secrets that surprise me,” he said. “I pick secrets that are different, or common and expressed in a new, interesting way.”

Warren said he tries to maximize the PostSecret experience.

“Every week there’s going to be sexual secrets and shocking secrets and hopeful secrets, arranged in a way that they’re connected so they’re telling a story about us,” he said. “I think of the Web site every Sunday as a new chapter in a book.”

Even Warren has his personal secrets within the PostSecret pages — one of his own in each book.

The 43-year-old hasn’t analyzed whether or not PostSecret will be his project forever.

“I don’t think about the future that much,” he said. “I just try and make decisions every day that are to protect the interest of PostSecret. I think there’s something really special that I’ve accidentally stumbled upon full of wonder and mystery that I don’t fully understand.”