checkers
This (previously JAVA "applet") supports one player and two player mode, and also no players, that is, computer vs. computer, which is a bit like watching the game of life on steroids.
Instructions..
Move a piece by clicking on it. It will be backlit in orange, and then click on the target square. If there is a forced capture elsewhere, the piece will be backlit in blue.
Check House rules to skip the forced capture rule and move as you please. This is how I learned to play, and makes the game unsolvable (checkers was solved by Schaeffer's Chinook team in 2007, years after this applet was written).
I found this nosing about the code at the old MIT ai (artificial intelligence) FTP server around the turn of the century. I've since improved it and ported it over to JavaScript, so it can live on for ever.