If you like to jump into water off cliffs, ask a boatman at Panajachel to take you to the cliff jumping spot near San Marcos. There's a nice ledge about 25 feet up, and for the really daring, you can climb quite a bit higher. The climb itself is an interesting challenge, looking for finger and toeholds, but you know that if you lose your grip, you can just push off and splat into the deep water.