Just a quick story. I was diving in Thailand years ago (I must have been 14 or 15) and had an experience I wont soon forget. My dad was my buddy, and we were being guided by a DM from the local charter. Mid dive a HUGE Eel cam darting out of a hole in the reef and right for me. I froze. The Eel proceeded to tap its fangs (big, big fangs) on my goggles in a rhythmic fashion. It then proceeded to wrap itself once around my chest and continued on with the tapping. My father, concerned for my safety withdrew his dive knife and was slowly swimming toward me, when the DM grabbed his arm and stopped him in his tracks. The DM then swam over, grabbed the Eel, untangled it from my body and gave it a big hug!! We were later told that "Ralph" the Eel was a regular at the reef and had been "trained" to interact with divers....not sure whether they meant trained or "fed" but either way he was apparently harmless. All i know is that my wet suit got real warm real fast, and i would really have appreciated being told about this "friendly" Eel prior to the dive.