I deliberately left the grounded extension cable to my MacBook Pro at home. At the time, something in the back of my mind told me I shouldn't, and that something was right. I brought an airline adapter which proved useless--my seat had a US power outlet. Unfortunately, the power brick wouldn't fit in the little nook where the outlet was. The extension cable would have worked perfectly. Luckily, I brought 3 batteries.
My room at the Hotel Nikko has US power outlets, too. My T-Mobile Blackberry Pearl works just fine, even as a bluetooth modem.
I'm sticking around for the weekend for a little a sightseeing. I plan on visiting the Great Wall, Forbidden City, etc. Drop me a line if you're in the area or if you have any travel tips.