Also known as DSL. A super small distribution based on DebianGnuLinux SargeRelease? that is under 50Megs with a choice of two graphical desktops - FluxBox? and JoesWindowManager?. It is a live cd that can be installed to a hard drive or USB key. DSL uses a 2.4 Linux kernel due to its smaller memory footprint.
Another flavor is DSL-N, DamnSmallLinuxNot?. It uses the 2.6.18 kernel and is slightly bigger, about 95megs. It is not as popular though.