Unfortunately, you didn't indicate which operating systems you're wanting to mirror but Windows 7 already includes the ability to create a System Image at any time.(Control Panel-Backup and Restore) Vista has a similar option.
As to earlier operating systems, have you thought about Acronis?
Hope this helps.
I'm trying to find a utility that will allow me to make my own Bootable Recovery CD/DVD. I want to make a complete system backup that can later be used to restore the system to the state it was in when I shipped it to a customer. I would rather not have to buy a new copy of the utility for each system that goes out but just one in house copy that can be used to make the CD/DVD without violating any licensing.