Many coffee shops, restaurants and pubs have loyal followings. But how do those small businesses convert the in-store traffic into digital evangelists on Facebook and Twitter?

Seattle startup SPARQCode thinks it has figured that out, and if you live in Seattle and frequent a neighborhood retail store you may have already encountered the technology. The company has rolled out its form of QR codes at more than 700 stories throughout Seattle, helping those businesses do a better job of making the leap into the social media universe.

"Local business owners routinely cite word of mouth as their most effective method of customer acquisition," explains founder Jesse Chor. "Social media marketing -- (for example) Twitter, Facebook, Foursquare, Yelp, Gowalla -- is like word of mouth on steroids, but most (small businesses) don't have the time or technical expertise to manage it effectively."

SPARQcode believes it can fill that gap.

Consumers who visit one of the participating stores -- including the Husky Deli in West Seattle and Garlic Jim in the University District -- snap a photo with their smart phone of the codes in order to be transported to the businesses Facebook or Twitter pages.

For merchants, the system is relatively simple.They visit the SPARQCode Web site, enter the name of their business, upload a logo and then generate signs which feature the 2D barcodes. It is free to print and display the poster, but merchants can decide to sign up for a special social media package that includes colored signs, display holders, window decals and more. That package sells for $19.95.

Small businesses appear to be warming to the idea, as are chains. Some of the trial customers include branches of Haagen Dazs, Jamba Juice, Jimmy John's and Subway.

The Artful Dodger tattoo shop in Capitol Hill has begun using SPARQCode's technology to drive Facebook fans.

Nicole Hardy, owner of Circa, a West Seattle restaurant, said that her customers are active Facebook users and on occasion even post photos of the food on the social networking site.

"The hard thing for us to know is how to utilize facebook better and promote that we even have a facebook page," Hardy says. "These signs help make it super easy for any customers to know about our facebook page and spread the word without us doing anything more than to just put it up in a place where they can be seen."

SPARQCode has raised $550,000 from a group of angel investors that includes Andy Liu, John Keister, Founder's Co-op and others.