Newish rule:

...you may not use contests as a means to directly bribe people into artificially boosting your leaderboard status, if that leaderboard pertains to a legitimate talent- or skill-based competition within the Forumwarz universe. Just as Klan-based voting is illegal in Forumbuildr, so is paying a user to vote up your submissions in Forumbuildr or INCIT. You also cannot bribe a player into colluding with you in Domination, for example. For reasons of practicality, the exceptions to this rule include the Most Popular and Top Flamebaters leaderboards.