Irrationality -- Episode 106, "The Socratic Method"

Clinic patients:
Mom looking to scare her daughter away from sugar
Guy with hiccups

Irrationality is the tie that binds: Wendy's mom trying to get House to scare her daughter skinny for purely selfish reasons; the guy with hiccups covering all the "normal medical bases" for getting rid of them -- "pulling the tongue, ice packs on the throat, hitting yourself, the groin pinch"; the extremely well-intentioned son of the main patient thinking he can take care of his mom all by himself with nothing but vodka and microwavable burgers; and finally the main patient herself, thought to be schizo for most of the episode until her one rational act -- calling Social Services on her son -- tells House otherwise.

The hiccups guy is also another one of those structurally functional clinic patients. Before House gets to him, Cuddy coyly tries to get House to fess up to his birthday (it's Wendy's too, for another link) and in the process gleans that something else must be going on with his patient. She picks up the phone for some investigative work, we cut to hiccups guy, then Cuddy butts in and we cut to the bathroom, where Cuddy confronts House about the tumor shrinkage. So what was hiccup guy's function? A sense of time gone by.

And for my day's good deed, here's how you get rid of hiccups: Control your breathing. Go sit somewhere where you won't be distracted, and breath in for 8 and out for 8 till they're gone. Works every time.