No one has ever tried it on me, but whenever someone tells me they have the hiccups, i tell them to prove it. MOST of the time, they can't. I don't remember where i heard this (probably here) or have any idea why it works, but sometimes it does.
This. Get still & quiet, with zero distractions. Breathe as gently as possible through your nose. Focus all your attention on the muscle in the base of your throat, concentrating on anticipating it tensing up at the inception of the next hiccup. If one slips through, just keep trying. With experience you'll be able to 'Zen' away your hiccups without as much concentration and with fewer slip-throughs.
I get hiccups after every meal. I have found nothing that has ever worked consistently except waiting it out. It annoys the shit out of my wife. She always pokes fun at me. Sometimes it makes me go to the corner and cry.
I had a band director who would call you to the front of class and tell you he would give you a dime per hiccup. He never had to give away any money. It must work. I have also learned to "zen" away hiccups by breathing very gently and being still and quiet. I have no idea why it works, but it does. Another thing that I did as a kid was a spoonful of vinegar. Just smelling it would make my hiccups go away.
Something that has always worked for me is to take a deep breathe. Hold it for 10 seconds. Without letting the first one out take another deep breathe and hold it for another 10 seconds. Then let out. Has never failed me.