I stopped at Cafe Amici, on the NW corner of Montgomery and Bush, for hot chocolate. A previous poster had heard good things about the coffee from a friend who mistook the name, but regardless of the name of the place it was the best hot chocolate I've had in the Bay Area.
First good sign: the menu has "hot chocolate" and "chocolato caldo italiano" as separate items, so they know the difference between stirring some grains of Ghiradelli powder into milk and melted a good amount of chocolate into a small amount of milk, European style. Second good sign: the chocolato caldo, at $4, was almost twice the price of the hot chocolate. Third good sign: the chocolato caldo comes only in one size, an 8-oz cup.
It was fantastic. Made with Chocolat Vitale chocolate, which is available in tins at the cafe, the chocolato caldo was truly chocolaty (even more than my beloved Cafe Madeleine's) without the heavy creaminess of Boulette's Larder's hot chocolate. I find that Boulette's-style creaminess cuts the sharpness of the chocolate too much. Instead, Cafe Amici's was sharp and rich without that congealing unctuousness I dislike in Boulette's. The chocolate itself was in the honey/caramel direction, which is my favorite chocolate undertone for hot chocolate.
This place is a branch of Cafe Amici at 15th and Potrero. It opened this month, I think, in what I believe was a Torrefazione Italia space. Their coffee is Caffe Umbria, which I didn't try.