Live CD/USB

UNetbootin is an alternative way to install different Linux distriubutions. It allows you to run the installation program off of a USB drive instead of a CD.

"Flow is the latest in the line of Hexxeh's hugely popular ChromiumOS builds. Flow is the most exciting version yet, bringing even more hardware support, an auto-updater, webcam support and an improved application menu & directory. All this, requires only a 2GB USB drive (download size is 327MB)"

Untangle is a free network management and firewall operating system.

FreeNAS is an open source Network Attached Storage operating system.

SmoothWall is an open source firewall operating system.

Debian is a Linux distribution with many of specialized features.

Mandriva is a popular Linux distribution for users who are new to Linux.

Linux Mint is a popular Linux-based operating system.

CrunchBang Linux is a lightweight Debian distribution.

MeeGo is a popular netbook OS.