The musty scent of a used-book store on a rainy Saturday holds the ultimate allure for me. And I know I'm not alone.

"Nothing sparks the memory so powerfully as scent," says Christopher Brosius, a Brooklyn perfumer who bottles a scent he calls In the Library, "a warm blend of English Novel, Russian & Moroccan Leather Bindings, Worn Cloth and a hint of Wood Polish." (2 ml for $12 at cbihateperfume.com)

A similar aroma lingers today in the city's nearly two dozen used-book stores. They struggle to stay in business in the face of intense competition from the Internet, and we who thrive on the joy of the hunt salute them for it.

Some used-book sellers have embraced the Net.

"We sell on the Net ourselves," says Greg Schirm, who owns House of Our Own with his wife, Deborah Sanford. The West Philadelphia store is about to mark its 40th year in business.

"Internet sales have given us a whole new clientele throughout the world," Schirm says, "and has helped to keep the store going."

But Molly Russakoff, of Molly's Bookstore near Ninth and Carpenter, says selling books on the Internet made her feel like a data processor.

"When you are selling online you're working for a huge, faceless corporation," Russakoff says. "The profit margin varies and it can be profitable, but it's not nearly as much fun."

Her parents were schoolteachers who sold used books in the city and at the Jersey Shore. Russakoff worked beside her parents along with her brother, Joe, whose Mostly Books has two Center City locations.

Sharon Bruce, who runs Mostly Books with Joe Russakoff, her husband, says that between the poor economy and the sustainability movement, there is a slightly larger core of used-book devotees.

"Some people say bookstores in general have gone the way of the buggy whip," says Greg Gillespie of Port Richmond Books. "But like vinyl records, books will make a comeback."

Gillespie does business in a former movie theater now crammed with a floor-to-ceiling collection of 100,000 volumes - heavy on Irish literature, detective and mystery books.

One cozy room there is furnished with a piano, a rocking chair, and an old couch for lounging. And if hunger calls, try Syrenka Luncheonette, just down the street at 3173 Richmond St., for pierogi or golabki.

Germ Books in Northern Liberties is one of several cooperatively owned specialty used-book stores. Here, "germ" refers to microscopic destroyers capable of taking over the Earth. E.T. could call home from this remarkably uncluttered shop and art gallery. Grab a snack at Rocket Cat Cafe, two doors down on Frankford Avenue, or brunch at Ida Mae's Bruncherie around the corner on Norris.

As the highlight of a lazy Saturday afternoon, used-book stores may still have a future.

Bindlestiff Books, a co-op in West Philadelphia, is seeking to expand its selling floor. And in Manayunk, Ann Tetreault just quit her day job at the Library of Congress in Washington to work full time at The Spiral Bookcase.

Tetreault and her fiance started the remarkably bright and cheery used-book store six months ago, initially offering weekend-only hours. But as of last month, they're open Tuesday through Sunday. Thirsty? Mugshots coffeehouse is next door on Cotton Street.

Contact staff writer Dianna Marder at 215-854-4211 or dmarder@phillynews.com. Read her recent work at http://go.philly.com/diannamarder.