I just saw this recent article on the scientific portal PubMed on a new way to treat hiccups: "Termination of intractable hiccups with digital rectal massage" Loosely translated, this research implies that as an added bonus your proctologist can now treat your hiccups.
Personally, I'll stick to trying to hold my breath to cure hiccups. I'm glad I'm an experimental physicist as opposed to an experimental biologist.