FlashBoot

FlashBoot is a tool to convert Windows XP/Vista/7 installation CD/DVD to bootable USB disk, useful for Windows installation on netbooks and other devices without CD/DVD drive. FlashBoot supports USB flash thumbdrives and USB hard disks.
Also, using FlashBoot you can create blank bootable USB flash with minimal set of system files and then manually tune it for your needs, or convert a full-featured bootable CD-ROM or floppy disk to bootable USB Flash keeping all functionality. Different operating systems are supported: Windows 7/Vista, Windows XP, SysLinux-based disks, GRUB4DOS disks, Linux kernel etc.
Click here for more info: http://www.prime-expert.com/flashboot/
Overview
Why USB disks?
Why FlashBoot?
Screenshots
Download Demo
Setting up BIOS

Try FlashBoot for 99% Bootability!  RMPrepUSB can make a USB drive bootable, but some BIOSes may have problems. If you need to create a USB drive that will boot on 99% of systems...Download

Download FlashBoot: flashboot-2.1m-setup.exe [32 Mb].
Limitations of demo version:

• USB disk or image file is bootable only for 30 days since the date of formatting
• Each distinct USB disk can be formatted by FlashBoot demo version no more than 16 times

Maximum time of use of demo version is not limited.
Demo version may be upgraded to full version later by copying license key file to FlashBoot folder, there's no need to download big files twice.
It is recommended to try out the demo before buying the full version to ensure that there are no hardware incompatibilities and product meets your particular needs.
System requirements for FlashBoot 2.x:

• BIOS which supports booting from USB devices
• Operating system: Windows XP, Windows Vista, Windows 7, Windows Server 2003, Windows Server 2008, either x86 or x64 edition
• 256 Mbytes of RAM
• 30 Mbytes of disk space

Portable version for users who don't like installers or need to run FlashBoot from removable media on multiple computers: flashboot-2.1m-portable.zip [32 Mb].