The players rate each other on the JTS MUSHes.

As a player that spends a great majority of his time on JTS I haven't seen any major issues with collusion from that angle. The main reward is that everyone who gets at least one +vote is given some recognition on the site for that month and they get a little experience (more if they opt to leave a comment to the player they are voting for). It isn't a great deal of experience and the most 'collusion' that goes on is that people vote for people they RP with a lot. That's part of the point of the system though, is it's an easy way once a month to let people know, "Hey, I like RPing with you." The votes are also anonymous so they don't have to know who voted for them unless you want to say so (I do like to sign mine when I remember).

Anyway, as a player I enjoy that little pat on the back that says, "Hey, you're pretty cool and you need to log that character on more often!" :>