in the bay area i have found that a flat-key U-lock and a cable for the rear wheel works pretty well. having said that, i fear my bike will be stolen (or at least my rear wheel) next time i lock it up. but the thing about the bay area is, there are nearly always a couple other bikes around, either locked stupidly or not locked at all, so the casual thief will avoid yours (again, i hope i will not be struck down for saying such a thing) if you just make sure the frame and wheels are locked down.

however, if my bike and yours were next to each other, and yours had a new york lock on it, mine would be a goner. so there's that to consider.