You could easily make it "anonymous" by just posting somewhere that "x players have requested to slow/speed up/pause the game." Then you'd have the option box at the bottom of the screen saying "slow/speed up/pause/nothing" (the last one being the default option.) This way, you might have someone who wants to slow it down, but someone else suggests a pause. Maybe the people that wanted to slow it down could go along with that.
You could even throw in a tab for paused games. Or perhaps just move them to the bottom of your list. (Right above the games that you've been eliminated from that are still active. :-) You might even just pause press, so that way, if someone wanted to "unpause" the game, you'll get a "mail" icon next to that game, and when you open it, you'll see a vote to unpause the game. Once you've seen the vote, the mail icon goes away, naturally, until someone else adds a vote (or that first person changes their vote.)
Hopefully this makes sense. If not, maybe I can explain it in better detail. I like this idea. But would we have set times as to what constitutes "slow/normal/fast"? Maybe slow = 72 hours/turn, normal = 24 hours/turn, and fast = 6 hours/turn. (Naturally these generalizations would only apply AFTER a game has started.) Just some food for thought.
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http://phpdiplomacy.net/board.php?gameID=4930
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