Girlfriend dodging aside, I think the ability to lock certain parts of the OS would be useful from a business sense. I would love to be able to lock calendar, email and documents while not really caring about the programs, internet, etc.
I know I can lock the whole phone, but there are plenty of times I give my phone to someone who I don't need looking at my agenda. I end up watching them as though they have a little copy of my life in their hands.
And SMS lock might come in handy too...
