Can't shake those pesky hiccups? Try a massage. No, not a back rub. Something, er, lower down. Doctors at the Bnai Zion Medical Center in Haifa, Israel say they cured a 60-year-old patient's persistent hiccups with digital rectal massage. When the problem re-arose, they went back to the well and were able to massage the hiccups right out of his system again [source: Odeh, et al].
So how did that work? Hiccupping is caused by spasms from cranial nerves called the vagus and phrenic nerves, which stimulate the area around the diaphragm. These nerves also send and receive signals from the thorax, gut and GI tract. So, if you have spasms in these nerves, stimulation from a finger up the rectum (which as you might guess is a sensitive area) might help. The vagus nerve, in particular, has a lot of innervation in the rectum [source: Scicurious]. Though the scientists recommend this treatment to others, no large-scale study has been done and this is probably one study that will have difficulty recruiting subjects.