curses:
 planets
 throwing a stone
 other animations

random stuff:
 coin flips
 random walk

word processing:
 text search
 concatenate files
 convert to lower case
 strip whitespace

games:
 tic tac toe
 guess the number
 checkers
 other card games, board games

math:
 calculator
 solve equations (quadratic formula, etc.)
 
quizzes:
 arithmetic test
 spelling test
 
etc.