nSnake is an implementation of the classic snake game with a textual interface. It is playable at the commandline and uses the nCurses C library for graphics. Its purpose is to provide a simply-coded, almost tutorial-like game with C. The source code is thoroughly commented.
DisPass is a passphrase generator that generates unique passphrases formed from a master password and a label, helping you get rid of the bad habit of using a single password for multiple Web sites. It is a console application, but it also has a simple graphical interface.
yetris is a Tetris clone which runs on the terminal. It has colors and high scores, along with many features found on modern Tetris implementations. It's made with C and runs on (most) Linux terminals.