Adobe Books in San Francisco's Mission District is at risk of closing its doors after 25 years. According to the owner, the used book store needs to raise at least $60,000 to stay afloat.

A rallying event earlier this week felt like church -- the homeless, and locals who can afford Mission rent all jammed in between rows and rows of obscure books.

Rebecca Solnit, one of many San Francisco authors who is an Adobe regular, asked how many people were English majors. Half the hands in the room shot up. "Oh my God," she said. "Can we have a secret handsign like the letter "E" or something?"

Before doing a reading, Solnit said defiantly, "You know, they're trying to convince us that books are obsolete. But I challenge you to show me an app that's going to last 200 years."

Owner Andrew McKinley says that to survive, Adobe has to be more than a used bookstore. He may start selling art and offering workshops. "We're creating a business plan that will work in the new economy," he said, "the new world that San Francisco is becoming."

To raise cash, McKinley is bringing on new business partners and launching a crowdfunding campaign on Indiegogo.