Also IN the bag (expanding this , hopefully not too much off-topic):
Olympus SW-type camera (Shockproof, waterproof to 33 feet):
This one has survived, where several others have not.
Lights:
Pelican (Sealed, waterproof, won't make spark/can be used in hazardous areas)
Although DS really likes SureFire Tactical lights, also sealed/waterproof... The LED is incredibly bright and useful, and bulb can be interchanged with incandescent one... LED wavelength just hilights steam(think car High Beam headlights driving through fog), incandescent one cuts through steam.
Ear protection:
Find Fastenal in your phone book, and see their selection of hearing protection, or look around the internet. The little foam things you can shove in your ear are MOST handy if your sea partner snores
Or if YOU do, and you want to make sure your sea partner can get some sleep.
And, although none of us smoke, if your Mid is traveling to lands where there is lots of sand or Cherry blossoms, you'd be stunned at how popular/valuable/sought after American cigarettes are... especially the red and white brand.