You may have used an hourglass (or "minuteglass") timer when you played a game like Scrabble. This is a "turn timer". Each player has a certain amount of time, like a minute, to complete each turn. This kind of timer is inherently unfair, and causes games to last longer than they should. They are unfair because they still allow slow players to make other players wait. They make games last longer because they encourage players to use all of each turn's allowed time.
The Multi-player Game Timer is better. It expands upon the idea implemented by chess clocks. Each player gets a set amount of time to play the entire game. During a player's turn, his clock is running. At the end of his turn, he hits the clock, which stops his clock and starts his opponent's clock. This approach allows you to take more time on turns that require more thinking, and less time on trivial turns. This encourages better play, and optimizes total game time.
Timer
If you need to read these, I have failed to make the software intuitive.
Before the game starts, the number of players can be set, their names entered, and the amount of time each player is allowed for the game can be selected. When it is all to your liking, press Start. The Next button makes it the next player's turn. The Pause button stops all clocks. You can use the Restart button to start over. This is useful if you finish a game, and want to play another game with the same players.
TODO: a toggle to choose how to behave when a player runs out of time (right now it assumes the player out of time has lost; all clocks are stopped)