Titanic Still Teaches Us - What can you do to stay safe at sea?

Safety on the water is always a concern.  I've enjoyed three Caribbean cruises, two house boats, many passenger and car ferries, and several city tour boats without incident, but I prefer to be overly prepared in any situation.  I searched for some good "Staying Safe on a Cruise" websites and blogs, but I came up surprisingly short.  Most information provided helps you steer clear of crime (pickpockets, abductions, etc.) on larger boats or cover basic physical safety on smaller craft.  Those are paramount to be sure, but when I step onto a boat, especially a big one, I want to think of the other things that might go wrong and be prepared to avoid or endure them.

• Food and water - On both of my most recent cruises, I took some snacks and bottled water, just in case.  They mostly sat there until the last day of the cruise.  But if there was a food contamination scare or if we had drifted for days at sea with no power, I was ready.
• Medical - On a cruise, you're at the mercy of the ship's doctor, who is likely not trained or licensed in the US.  But it wouldn't take a very large emergency to overwhelm any ship's medical staff.  I take at least a two week supply of medication with me when I travel, plus I take a few days worth of over the counter medications for common ailments (headache, diarrhea, etc.)  I also take an expanded first aid kit to include supplies for more extensive first aid.  When traveling out of the country or to secluded locations, I often ask my doctor to prescribe an applicable course of antibiotics to have on hand, just in case.
• Power Loss - When mechanical or electrical problems occur on a cruise ship, things tend to get very dark very fast.  I always carry a single AAA battery flashlight with me.  In total darkness it's enough to get around.  I also keep a larger, brighter LED flashlight (that takes 3 AA batteries) in my purse/briefcase, my suitcase, or my room.
• Evacuation - When you arrive on the ship, you must to participate in a muster drill before the ship can sail.  Study after study shows that under stress, we will do what we have already done.  If your cruise should have to abandon ship, this will help you get out quickly.  Read the muster instructions, participate in the muster drill, talk with your group about the drill, close your eyes and envision each step of the muster drill, walk the path from your room to your muster station repeatedly (perhaps casually on the way to dinner.)
• Communication - In a ship's emergency, assume power will be out.  Get your group together and stay together.  (Remember you talked about this at the muster drill.) Plan ahead for some form of communication if the power were to go out and you might be separated.  (Exactly where will you meet or leave a note?)  IT is good to note, shortwave and HAM radios are often used at sea.
• Know Multiple Exits to Open Air - During a ship-wide emergency, you must go to your muster station just as you practiced.  But what if the path is impassable?  Once you've memorized the path to the muster station, start exploring the ship, including different ways to reach higher and outside decks.  This will help you get around for the duration of the trip and in an emergency.
• Fire - Fire is a ship's worst enemy.  There are instruction in your room about fires, rules for items on the balcony to prevent fires, smoking restrictions, candle restrictions, and many regulations behind the scenes to protect a ship from fires.  Despite all these measures, fires aboard ships happen.