When I found myself at the beach, I pulled my sandals off and walked up the beach and then back, for about an hour and a half. Waded in the ocean a bit, got my feet all sandy, and even got my clothes wet and sandy. Woo! :-) Lots of sun, lots of fresh air. Maybe tomorrow I'll go back... with my bathing suit!
The ferry itself just takes a few minutes, and only costs 50 cents for a pedestrian. Presumably if you were in a car, you could go around the bay, but that might take longer than just taking the ferry across for a couple of bucks.
On the way back, I spotted a little shopping mall, and walked over to see if I could get some beverages to put in the hotel room refrigerator. Bought a 12-pack of 12 ounce water bottles. Today's food has been pretty simple... I had a roll at a bakery on the island, and then a chicken teriyaki bowl and some unagi at a small Japanese place with only a dozen or so seats on the peninsula.
I've cooled off for the better part of an hour, grabbed the photos from the camera and such, and I'm now going to put my bathing suit on and go relax in the shade by one of the pools until others start to arrive. The flight numbers Mike gave me show they hit DFW a few minutes early and will leave there in about a half hour.