So I'll be heading to Japan in a few weeks. I've never used a cell phone internationally, and I'm wondering if anyone knows what my phone will be capable of doing in Japan and how much these things will cost. For example, can I roam in Japan or will I get no service? Do I need to stay in airplaine mode the whole time? I'm assuming my 3G won't work at all and I'll have to find wifi hotspots. Any info helps.