Charge Throw

 
Prerequisite(s): Improved Unarmed Strike
 
Benefit: When an opponent charges you, they provoke an attack of opportunity from you that can only be used in an attempt to trip. If your trip attack is successful, then your opponent ends up prone in the direction of the charge 5ft. from you, and his charge attack automatically fails. Your opponent cannot attempt to trip you if your trip attempt fails.
 
Source: Beyond Monks