Applet the board game Othello. User can play against the computer or against another human. The computer's strategy consists of a moderately-sized opening book and a minmimax algorithm, along with a few heuristics.
Players can choose pieces and play Othello, with options to undo moves and view available moves on the board.
Thanks to http://www.samsoft.org.uk/reversi/openings.htm for listing some openings used by well-known players.