GNU nano is a GPLed clone of the Pico text editor. It aims to emulate Pico as closely as possible, while possibly adding new features.
Nano has moved to Savannah. Please see http://savannah.gnu.org/projects/nano/ for current releases.
This is a great editor, got to know it on linux a while back and instantly like it, its super easy to use and can be carried on thumb drive everywhere without needing to install it on each setup. Recommended