Exercise your brain while trying to defeat your computer in this entertaining strategy game. TicTacTotal has been a popular mental challenge for more than a decade. With version 1 lost to the Macintosh archives, here's version 2 for a new generation.

Playing the game is easy. As in Tic-Tac-Toe, players claim squares with an 'X' or an 'O'. However, the board is larger and getting 3-in-a-row doesn't win. Each square has a random point value. Claiming 3 consecutive squares adds to your total score. Once all 25 squares are taken, the high score wins. Figuring out which square to pick is the challenge. You need to figure out which square will give the most points and when to block your opponent.

Specify the computer's skill level or play against a friend. Select the range of the point values (positive, positive and negative). Finally, don't click away from the word Total. We can all benefit from honing our mental math skills and it really does become effortless.

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