I'm an American ex-pat living in Tokyo. For me, a trip to work or a trip to the in-laws or a trip basically anywhere on the train or subway very easily fills up my maximum 10 hits with new contacts. I have over 1000 at this point, and I don't very often take my 3DS out with me. I'm on a rare trip home to the US now, and I got all of one hit during my four-hour layover in San Francisco, nothing in the Chicago Airport, nothing in Atlanta. Needless to say, no hits in semi-rural Georgia. So is Street Pass pretty useless for most people?