There is another option, it's what I do. I have a dual non GSM AT&T telephone for within the United States. When I travel I have a triband GSM with an AT&T sim in it for use out of the country. Same number, etc. Yes there is a monthly fee ($8 or so) and yess the per call charges are up there (though not sky high), but having one number here and over there, as well as still having a telephone that can go analog over here when I am out of reach of a digital tower) makes it worth it to me.