Now that many Intel Mac users have a Windows Boot Camp partition on their Macs, backing up or restoring that Boot Camp data becomes a bit challenging, as most backup utilities only copy the Mac partitions; if you want to create a bootable copy of your Windows installation it's even more difficult. That's where tools such as Winclone, or Mike Bombich's NetRestore, come in; they allow you to easily make a disk image of your Boot Camp partition, which you can then restore to a separate volume, save for archival purposes, etc.
Winclone can also be used to quickly deploy a Boot Camp image to a number of machines (e.g. in a lab). Mike reports that he recently used Winclone to successfully reimage the Windows side of 10 iMacs with only a few clicks, sending the image package and the install commands via Apple Remote Desktop. Comparing it to NetRestore, he likes Winclone better: "Using NetRestore requires a separate install of the ntfsprogs toolkit to add the NTFS restore tools. Winclone bundles the ntfsprogs tools and a Perl restore script in with the image, so it's portable -- just copy the image and run the script to restore the Windows boot environment."
Winclone is a free download from twocanoes software, and donations are requested. Macworld's Mac Gems blog has a thorough walkthrough of backup and restore of Boot Camp using Winclone.