A rule originating on the Something Awful message boards that calls for the banning of a member who does not follow his own proclamation. These proclamations are typically in the form of "If X happens, I will do Y." The person who posts the claim is asked to follow through with his promised act or be banned for lying.
This rule originated from a forum member, Toxx, stating he would tape together the parts of his nether regions if a message board topic reached 5,000 replies. The Something Awful Administrator ordered that he post pictures of the completed act. No pictures were produced, and Toxx was banned as a result. The Toxx clause was instituted as a rule to discourage future members from making exaggerated claims.
Example poster 1: "If he sells this laptop to me for $200, I will eat my shorts."
Example poster 2: "Sell it to him just so we can test the Toxx clause."