Here is a fun word game: transform 'plane' to 'solid' substituting one letter each time, no rearrangements, additions, or deletions, each intermediate step must meet some standard of goodness like 'legal in scrabble'. Make up your own start-end word pairs! 5-letter words are just right, 4-letter too easy, smaller or larger are just about impossible most of the time.
Use of computers for the game is considered cheating. 'cloud' -> 'clown' is also fun.