The Museum of Questionable Medical Devices, now closed, contained over 250 items. Some of these are now on display at the Minnesota Science Museum in St. Paul.
Here are three devices from the collection.
The Battle Creek Vibratory Chair:
This is from around 1900, and was created at the Battle Creek Sanitarium, directed by Dr. John Kellogg, of Corn Flakes fame. It was designed to stimulate intestinal peristalsis, and cure back pain and headaches. it looks about as comfortable as an electric chair.
The Radium Ore Revigitator:
From 1925, the idea behind this was many health problems stemmed from "denatured' water lacking an essential ingredient : radioactivity! A little radium was the ingredient needed to keep you healthy. Um, not exactly.
Here is another painful looking device, the Prostate Gland Warmer, "designed to stimulate the abdominal brain".
Here is Bob McCoy, curator of the museum, on Late Night with Conan O'Brien (1998)
Many more videos can be found at the museum's You Tube channel.