So, this might seem a little silly, but after a season of chasing soda cans and water bottles around the boat, we realized that we needed a solution. The open gunwales have been useful for so many things (plus they look great!) and I thought I could find another use. So, employing a bit of leftover occume plywood and some mahogany, I made the following:

The cupholder will hold a small bottle of water like this one, or a big 24 oz. soda, etc. They cna be moved around anywhere, and, as a bonus, they float!

Front View.

Just the right spot for the person at the helm. If you like the design, and happen to have open gunwales, I would be delighted if you would copy them....