Just discovered another annoying thing about the N1 and apparently with all Android phones.
The OS doesn't allow tethering - that is using the phone as a modem via BT or USB. Apparently the US telco's ban tethering so that Google in order not to get offside with them, disabled that in the phone.
I find this a very useful capability and was initially annoyed. There are a couple of solutions out there though. One is to root the phone and install custom code to enable tethering; something I am not keen on doing. The second is to use the app PDANET which does not require rooting the phone but costs $23.95(US) for full access (BT and USB) or free if you only require access to non SSL sites.
I am surprised nobody has mentioned this before here. Certainly given the costs of data plans in NZ, I doubt whether TNZ or Vodafone really care if you tether the phone or not since it's all data to them.