The title of Season 3 Episode 15 is...

Walk on Water

and here are some spoilers on it from SpoilerFix:

A woman with pieces of glass in her chest comes to the ER looking for her husband who was in another ambulance. She refuses to be treated until she sees her husband. Question is, is he at Seattle Grace? A doctor has to deal with rather angry people complaining that the wait to be treated is way too long. Somewhere in Seattle, a doctor helps a man stuck in his car after he had an accident. A patient is hopeful after eye surgery. A very lonely child waits alone in the waiting room while her mother is being treated by doctors.

The episode is currently slated to air in Febraury 2007. More information to come.