A couple a weeks ago I took the ferry out to Tsuken Island about 15 minutes east of Okinawa to shoot their annual Dragon Boat races. Tsuken is one of the islands I can see from my home (although I didn't figure this out until after I got back).
Everyone there is pretty much either a fisherman or a farmer, with carrots being their crop of choice.
While you can rent a bike for the day for ¥500 (about $5.00) and ride around there's not much to see really. I'm told that the waters around the island are great for snorkelling however.
I think I was the only foreigner on the island that day but I was welcomed with open arms and treated very kindly by everyone.