Long story short, Rincon is really cool. There is, really not a whole lot to do that is not ocean related. They are famous for surfing and the like. I don't surf, and am not a fan of swimming in the ocean (do you know what lives in there?) but even so, I really liked it. It's a very laid back kind of town, and every body seems to live and let live there.
Down near the hotel was this small marina which had long since had the sand close off its access to the sea. I can't imagine that made the locals really happy.