BitLocker first reared its head in Windows Vista, but the scope of the encryption software has been extended in Windows 7. Since Vista's launch, lost or stolen USB drives have become an enormous security liability.
Microsoft's response is BitLocker To Go - encryption for external USB drives (either flash or hard disk), which is activated with little more effort than a right-click on your chosen drive in the Computer menu.
Encryption is by no means a speedy process: a modest 1GB flash drive took in excess of 15 minutes to encrypt, although you can carry on working while Windows beavers away.
Once encrypted, the drive can be only accessed by entering a lengthy password or (if your company supports them) swiping a smart card. You can set your encrypted drive to work on your regular work PC without entering the password each time.
The BitLocker-protected drives work on XP, Vista and Windows 7 PCs, although XP and Vista machines can only read and copy files from encrypted drives and not write to them. Macs are predictably befuddled by the whole affair and refuse to deal with BitLocker.
What happens if you forget your password? BitLocker To Go provides a 48-character recovery key, which can either be saved as a file on your work PC or printed out and (preferably) locked in a safe somewhere.
The recovery key can be used on any PC, not only the one you used to encrypt the drive, which means IT departments can manage the entire recovery process (storage of the keys and data recovery) if they so wish.
BitLocker security for internal drives remains largely unchanged: you'll still need a TPM (trusted platform module), and you might want to encrypt the drive overnight, as even our modest 60GB drive took in excess of an hour-and-a-half to complete.
Microsoft, in its infinite wisdom, has once again decided to restrict BitLocker to the Enterprise and Ultimate versions of Windows 7, shamefully leaving the "small business-friendly" Professional version without a native encryption solution.
Also in this series:
Part 11: Designed for Touch
Part 10: Wireless that works
Part 9: Turbo Boost your laptop
Part 8: Hunting down those missing files
Part 7: Good news for gamers?
Part 6: Blu-Ray and displays
Part 5: The new XP mode
Part 4: Playing DivX and XviD files
Part 3: Will your PC actually boot any quicker?
Part 2: Raw performance benchmarks
Part 1: Good news for gamers?
Also see: The 30 Best Features of Windows 7