I always have these three things in my pocket- keys, a small knife and a rechargeable flashlight.
Here's a photo - I don't have my keys here, the key is a car key.
The knifeWhen I was a seaman, Coast Guard Chief Warrant Officer Wilson told me never come out on deck without a knife. That was over thirty years ago. As I advanced in rank the knife has gotten smaller and smaller. I like this one because it is flat and you don't notice it in your pocket.
This light is perfect for the wheelhouse. It's rechargeable and like the knife, is flat. There is a better picture here. Outside on a dark night or in the holds the beam gets swallowed up by darkness so you'll want to grab something bigger for that. Still, it's better then nothing.
What's in your pocket?