When we ask our savvy mavens where to go for champagne, they say D&M without pausing. This unassuming corner store in Pacific Heights is said to be the preeminent source of mail-order champagne in the US. It's not surprising that the stock is vast and the sales people infinitely knowledgeable. Impress your friends with a 1959 bottle of Dom; and if you want to show off to your wine-snob best friend, Champagne vintners like Serge Matthieu, Palmer, and Pierre Gimonnet et Fils are sure to win her over.