Iam looking for a metal or plastic cabinet/box that is around 12" x 12", I can deviate from this measurement some.  Probably not too thick, somewhere from 3" to 5", and a couple of shelves in it.  I want to install this in the boat for fishing glasses, some small tools, stuff like that.  I cannot locate anything online, so I thought I would ask here and use a few more brains than I have.  My first thought was like a lock box with a hinged lid that I could turn to create a cabinet, but the ones I have found are too small.  The other idea I had was something like a first aid kit that hangs on the wall.  I know, crazy question, but I had to ask.

Thanks-Arlo

If you're a little handy with tools, you can easily make one yourself out of some thin gauge aluminum.  It bends really easy and you'll be able to make it whatever size you want.

Get one of those metal selves with the little plastic drawers in it.  You can use the drawers or remove them and just use the selves.  I have a ton of these in the basement full of all sorts of stuff from screws to nuts and bolts.

What about a few of these?

http://www.organize.com/accomdistow.html

You could cut a thin piece of some wood or something to make the dividers whatever size you want. You could stack them to fill the space.