Every country has methods for treating sicknesses that differ from other places. This isn't really something that surprised us. What has surprised us is the combination of traditional treatment methods and modern methods that are found in Indonesia.
I found this treatment tool at a pharmacy, alongside tylenol, thermometers and other various modern medications. It is used for what I will term "coining" (not sure that is correct).
In Indonesia there is a concept of a disease called "masuk angin" (enter wind). Any air that escapes your body in any way is caused by masuk angin. And most general malaise and maladies are also attributed to this. Everyone I have talked to, from uneducated villagers to college graduates, when you mention coughing or other ailments will tell you that you have "masuk angin".
Now, if it was just a name for a general feeling of sickness, that would not be an issue. The problem is the concept of how this disease is contracted. You contract "masuk angin" by standing in front of a breeze.
Indonesians are scared to death of masuk angin. In a country of motorcycle drivers (the whole country drives motorcycles) this is potentially disastrous. So what do they do? They cover up like they are driving through the polar icecaps while on their motorcycles. They don't turn on or stand in front of fans, air conditioners, etc. If they find themselves sick, they sit in a closed up room with no fresh air, trying to prevent further air from forcing its way into their body.
So how does this treatment work? If you can't get rid of your wind out of your body on your own, you used this little device to help. You maybe use a little oil and rub this coin on your back over and over again. If you do it right, you end up with long stripes of bruises/welts on your back. There are a good many kids/adults around here that sport these stripes.
The existence of these ideas isn't that amazing... but the mixture is. Educated people who should know about germ theory and even medical personnel still espouse the benefits of rubbing someones back to facilitate the speedy exit of... wind.