Estimated time:
Mere minute or so.

Number of servings:
one

Ingredients: (Hit your return key to start a new line)
a 1/2 cup of water
a coffee filter OR paper towel
(rubber band, optional)

Directions:
Wrap a paper towel or the coffee filter tightly over the top of the cup; consider a rubber band to secure it so a child won't spill all over clothes (although that might be a cure, too...)

Anyhoo, the strategy is, you ask the hiccup sufferer to sip the water slowly through the filter/paper towel. The towel should begin its mission dry; the time it takes to percolate through is probably part of what makes this work.

Other suggestions and comments:
My son's kindergarten teacher had to excuse herself from class briefly when her hiccups got so bad the children were 2 highly amused! The secretary ("Dr Joanie") had the miracle cure. I saw it work then, and my daughter (12) used it tonight with success. It can't hurt to Try It, next time you get the opportunity.