If you want to protect your data then the Bit Locker technology in Vista is a good way to go, and I would also recommend Vista backup as it's so simple to use .
Of course if you're in New Zealand and someone has broken into your office and swiped your laptop with your kiwi :-) data like Paul Croucher then you can also use the beer locker approach. This simply entails offering a reward of 12 bottles of beer a month for life - check the links if you don't believe me.
Bit locker is also built into Windows Server 2008 so that if someone lifts your branch server they haven't got your data.
I like the beer locker best, must make one