I like how GT (Gold Token) Game site does their ladders also.

First - when you join a ladder, you start on the bottom rung (Called Rung 1) Every night, people who are not playing a game are randomly paired up to play each other.

At the end of a game, the winner moves up a run, and loser moves down a rung (unless you are already at the bottom rung 1, then you stay there.)

So the winner will move up to rung 2. Even night, the system checks to see if there are available players on each rung - if at least 2 players are on rung 2, they will be matched up. Winner of the match will move up to rung 3, loser will move down to rung 1.

Sooner or later, you will get the best people very high up on the rung.

Other minor rules are:

1) Every couple of months or so, they remove any rungs which are empty, and drop the high rungs down. (So if 1 player is in rung 9, 0 players in rung 8 - rung 8 will disapear, and player in rung 9 will drop to rung 8)

I think there is a rule where you can not play the same player twice in a row. Each person has to at least play someone else before they play each other again.