Loved the Trash-80 so much. I consider myself lucky to have used one when I was a child. My favorite game was Android Nim:

http://www.trs-80.org/android-nim/

When I was young I thought that game was unbeatable and the adults who could beat it had a secret code or something. Now I realize it just plays a perfect game but you can win if you understand it.

Oddly enough one of the movies that I remember best when I was a child was also (seemingly unrelatedly) called "The Secret of Nihm"

http://www.imdb.com/title/tt0084649/