THE ABJECT BLANDNESS of the warehouse at 939 SE Alder St belies the creative party going on inside: Egg Press’s clan of 12, grooving to indie rock while cranking out 30,000 handmade cards a month on the company’s seven letterpress machines. The festive environment isn’t just a company perk, says owner Tess Darrow, but an essential part of producing cards full of wit and whimsy.

The revival of the letterpress—a 15th-century machine that pushes images into paper instead of printing them on top like most modern printers—was just beginning when Darrow launched Egg Press in 1999 by bringing a collection of her handmade cards to the San Francisco Gift Show. Twelve years later, Egg Press cards can be found in more than 800 stores (albeit none of their very own; the Alder “shop” opens to the public only for sample sales and consultations for custom printing jobs).

Egg Press’s inventory, which favors hand-drawn designs reminiscent of (cool) yearbook illustrations, has expanded since those early days to include posters, gift wrap, and—take note, newly engaged—custom invitations. Last summer, the company partnered with calendar giant Blue Sky to produce a line of datebooks and calendars now available in 1,700 Target stores.

“I used to worry that selling greeting cards wasn’t enough to better the world,” says Darrow. “But when I think about the joy of opening a card, the millions of cards we’ve put into people’s hands, and the messages contained in them … it’s a bit overwhelming."

We’ll say. By our count, that nondescript building on Alder churns out roughly 360,000 smiles a year. Find yours.