Whoever said that nothing in life is free has clearly never been to the Bay Area Free Book Exchange, where each weekend patrons are free to peruse the cluttered and haphazardly stocked shelves of the El Cerrito book “store” and emerge with an armload of books entirely on the house. To date, the exchange has given away hundreds of thousands of books — including campy romance novels, travel guides, and indisputable classics — amassed entirely from donations. (Organizers sell off some of the more valuable books on eBay to keep the otherwise nonprofit operation afloat.) To ensure that crafty patrons don’t profit from the gratis titles, each book that exits the volunteer-run shop is marked by a red stamp that warns: “Not for resale. This is a free book.” The only other stipulation is a gracious one-hundred-book limit per person, per day. One hundred books for zero bucks? That’s quite a steal.