Nano Linux on USB flash drive 

NanoLinux is an open source, free and very lightweight Linux distribution that requires only 14 MB of disk space including tiny versions of the most common desktop applications and several games. It is based on the Core version of the Tiny Core Linux[7] distribution and uses Busybox, Nano-X instead of X.Org, FLTK 1.3.x as the default GUI toolkit, and SLWM (super-lightweight window manager). The included applications are mainly based on FLTK.

Applications included in the distribution
Nanolinux includes several lightweight applications, including:

Dillo graphical web browser
FlWriter word processor
Sprsht spreadsheet application
FLTDJ personal information manager
AntiPaint painting application
Fluff file manager
NXterm terminal emulator
Flcalc calculator
FlView image viewer
Fleditor text editor
FlChat IRC client
FlMusic CD player
FlRadio internet radio
Webserver, mount tool, system statistics, package install utility.

The distribution also includes several games, such as Tuxchess, Checkers, NXeyes, Mastermind, Sudoku and Blocks. Support for TrueType fonts and UTF-8 is also provided. Nanolinux is distributed as Live CD ISO images, installation on flash disk and hard disk[9] is documented on its Wiki pages.

System requirements
Minimal configuration: The Live CD version without swapfile requires 64 MB of RAM and 14 MB of disk space.[10]