I've seen a Thanks mod used on a vB forum, but I don't know where to get it. If it adds to the user's rep, then it would definitely be a good idea.
As for adjusting how much rep to give, that would be cool, but that would also make us lose the benefit rep receivers get when a user with a lot of positive rep gives them some.
Another cool thing to see is + and - buttons on a post, which would make it a lot easier to rep people, like on IP.Board.
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