I penned a rather large account of the Lucha Libre, Mexico's campy, but increasingly popular, version of professional wrestling: http://www.theglobeandmail.com/servlet/story/RTGAM.20071130.lucha01/BNStory/specialTravel/home
The Lucha libre is good fun and worth taking in during a trip to Mexico. Shows are staged regularly around the country, although the epicenter is the Arena Mexico in Mexico City's Colonia Doctores.