If you are thinking of getting a subsidized Google Nexus One be sure to read the fine print in the contract because it will cost you a grip to cancel early.  Not only will you have to pay a $200 early termination fee to T-Mobile, Google has their own version of an ETF called an Equipment Recovery Fee which is an additional $350.

You’ll end up spending significantly more to cancel your plan than it would to just buy the device unlocked and unsubsidized up front.