I think a better marketing gimmick would be to distribute these things to villages in impoverished nations and then to show the villagers logging into office 360. "If rice farmer mi ling from this is rural chinese village can use 360 out of the office, so can you!".
It would be great for the recipients as well, especially if lasted longer than 15 days.
Correct me if I'm wrong, but the current Microsoft stunt is using a T-Mobile portable WiFi connection, so is only possible in the US. For any other countries, unless they'd tied up with a local provider, this wouldn't really be possible.
I have T-Mobile in the US, but in practice I get a different T-Mobile prepaid GSM SIM when I visit the UK.
I haven't actually looked at what the international costs are, just heard enough horror stories that I take the US SIM completely out of my phone before takeoff.
It would be great for the recipients as well, especially if lasted longer than 15 days.