We love stopping for gas at the Xtension Food Mart on Rainbow a few blocks north of KU Medical Center. Every time we fill up, we get to groove to the cool, dirty, greasy blues blasting from speakers near the pumps. Most of the time, we don't even know who's playing, but the steady driving beats, mournful electric guitars, pounding piano jams, wailing saxophone solos and sad stories that make a person feel better — well, that stuff's just in our blood. Because we live in Kansas City, damn it. This sort of music should be playing on every street corner in the metro. "We play it all day, every day," says owner Shon Ledbetter, a lifelong Kansas City boy. "I've always been a blues fan." As a teenager, he fell in love with Chuck Haddix's Fish Fry and Bill Shapiro's Cyprus Avenue on KCUR 89.3. "I got a full-on education in music from those programs," he says. That obviously translates into the way he runs his convenience store. "I just wanted to do something to set us apart from every other store you go to, and it's been the most welcome, complimented thing that we've done."