Primarily my calendar and contacts, though occasionally a Microsoft Office document sent via Documents to Go.

I tried to sign up for the 60-day trial of MobileMe but gave up after the system booted me out after the sixth or seventh unsuccessful try to register. I read somewhere MobileMe has largely been a flop? I haven't looked at the Google stuff yet but may give it a try. I'd rather not keep a load of stuff in the "cloud" so it would be so much simpler if there was just a way to directly sync the iPhone/iPod with the iPad via Bluetooth or Wi-fi. It seems there should be an app for that.