UNetbootin

This installation mode creates bootable USB flash drives and bootable USB Hard Disk Drives; it is a Live USB creator.[3]

• Cross-platform (available for Windows, Linux and Mac OS X)[3]
• Non-destructive install (does not format the device) using Syslinux.
• Supports mainstream Linux distributions, such as Ubuntu, Fedora, openSUSE, CentOS, Gentoo, Linux Mint, Arch Linux, Mandriva, MEPIS, Slackware as well as FreeDOS, FreeBSD and NetBSD.[3]
• Can load a variety of system utilities, such as Ophcrack, BackTrack.[3]
• Other operating systems can be loaded via pre-downloaded ISO image or floppy/hard drive disk image files.[3]
• Automatically detects all removable devices.[3]
• Supports LiveUSB persistence (preserving files across reboots; this feature is for Ubuntu only)

Multiple installs on the same device are not supported.

This installation mode performs a network installation or "frugal install" without a CD, similar to that performed by the Win32-Loader.[4]

UNetbootin's distinguishing features are its support for a great variety of Linux distributions, its portability, its ability to load custom disk image (including ISO image) files, and its support for both Windows and Linux.[5] Unlike Wubi, and similar to the Win32-Loader, when installing to hard disk, UNetbootin installs to a partition, not a disk image, thus creating a dual-boot setup between Linux and Windows.[4][6]