And and I took a day trip to several of the islands off Nha Trang. The whole day cost 6 pp and included snorkeling and free wine as we listened to the crew, using very modest instruments, put on a "happy hour" show.
Here's a video of the Bloukrans Bungy in S Africa. I did this when I was here three years ago. Because I knew what i was in for, I passed up on doing it again.