Actually, I'm using one now. Last year I was diagnosed with early stage bladder cancer. Strangely, the primary treatment for it is called CBG, and involves dribbling in a couple of ounces of active tuberculosis virus in the bladder, lying on each side for 15 minutes and then expelling it, using bleach in the bowl for about 15 minutes to kill the virus.
The way is works is that the TB virus apparently attaches to the cancer cells in some way and the body's normal immune system then immediately attacks the TB virus and, after the TB virus dies, it's expelled. That only takes a day or so and back to normal. It's easy, not very uncomfortable and, in my case at least, the cancer was gone after the first 6 weeks of treatments, one a week. Since the cancer is highly recurrent, there are continued treatments, farther apart over time as long as there is no recurrence.
I was amazed that this has been the protocol for bladder dancer since about 1990. I have no idea how they figured it out, but it sure is great to have an easy treatment for a curable cancer. If I am going to have cancer, I like that it is easily curable.
So, there you have your example, although I see you are no longer a member.