The Sci of Fi: Here's an article on The Science of Super Heros from National Geographic.

Here's the Insultingly Stupid Movie Physics site refrenced in the article.

An exerpt from that site's review of The Abyss:

Harris decides to stay on bottom which proves to be a wise move. He's taken in by the aliens who place him in a room and do a Moses-style parting of the waters to provide him with a breathing space. They turn on the TV to make him feel at home and the reception is exceptional. This is all the more impressive since they're on the bottom of the ocean and no human has ever figured out how to transmit electromagnetic waves at TV frequency through salt water. Apparently they have cable.