BitLocker, first introduced in Windows Vista, has become an important encryption method when it comes to increasing security of laptop computers by encrypting the hard drives.
In Windows 7 beta, you can take security one step further by making use of the BitLocker encryption feature for USB flash memory, external hard disks and other removable media.
All you have to do is right click on the drive to be encrypted and choose Turn on BitLocker…
Organizations can also enforce all users to encrypt removable devices using this feature. IT administrators can manage this centrally via group policy that requires all USB drives to be encrypted even before files can be written to it.