Does anyone have a good place to buy a pre-paid SIM card with a US number for travel in Europe? Specifically, we're going to Ireland and France. Having 3G data access would be nice as well. I know I can buy them at airports over there but I'm assuming they wouldn't have a number based in the US for family to call in case of emergency. Further, does anyone know a good pre-paid micro sim for iPad 3G data? Thanks ahead of time!!