Never organized one but played in a few. Here is the jist of the format with a few tweaks I've seen implemented.
1. List of all player's names on a board with a win column and loss column.
2. All players randomly paired up on random machines with 1 person standing in what will become a 'player line'.
3. As the first game ends, the loser stays at the game, the winner goes to the board and marks a hash by his name in the win column and a hash by the loser's name in the loss column. The winner goes to the end of the 'player line'.
4. The first person in the player line then plays the loser waiting by the machine.
5. As games progress, the loser stays at the game and the first person in the player line goes to that game.
6. This keeps going for a predetermined amount of time like 2 or 3 hours.
7. At the end of the time, the winner is based on best percentage of wins vs losses.
Now the differences I've seen are that a loser can get stuck playing the same game over and over again. So after losing 3 times in a row on the same game, the winner stays at the game and the loser goes and marks the win and loss and stands at the end of the player's line.
Another variation I've seen is that the loser can either decide to play the same machine again or has the choice to play any other available game. This way they can go to a game they think they'll have a better chance of winning and not get stuck on the same game 3 times in a row.
It's a basic rotation of losers staying at the game and winners getting in a line. The person at the front of the 'player line' goes and plays the available person standing at a game. The player line usually moves pretty quickly; so there really isn't a lot of time standing around. The few I've played in no more than 2-3 minutes waiting. Compare this to strikes tournaments or group matchplay tournaments where you have to wait for everyone to finish a round.