Bruce Schneier links to a good idea for a two factor authentication system for internet banking.

All large value transactions for customers of ASB and Bank Direct will have to enter an 8 digit security code within a 3 minute window to authenticate the transaction - The code will be sent to the customers mobile phone.

I only hope the implementation of this doesn’t allow the user to setup there mobile phone number within the system through the internet banking system - otherwise surely this doesn’t provide any benifit at all!