This is pretty interesting news. Windows Defender sounded like a bad idea before it came out, but has actually grown to be pretty good at what it does, and this will make it extremely useful. The only problem is most of the public will have no clue about installing it to a flash drive so it can run before windows.

Check it out:
http://news.cnet.com/8301-10805_3-57...tside-windows/

Microsoft is launching a new version of its Windows Defender antivirus tool that will run before Windows even boots up.

Making its debut as a publicly available beta, the new Windows Defender is designed to run directly off a CD, DVD, or USB flash drive to scan your PC outside of Windows. As such, its aim is to detect rootkit viruses and other malware that can infect your computer during the boot process.