Penis Luigi

A phrase often uttered in response to something to which you didn't know how to respond; A phrase so nonsensical it immediately wins any argument and bests other nonsense, causing all forms of argument and nonsense to cease due to extreme confusion on everybody's part.

(Please note that there have been rare occasions in which a person who hears 'penis luigi' responds as if it made complete sense, and even agrees with it. This could be due to levels of confusion so high that a brain lesion occurs, causing the hearer to go into a fit of temporary insanity.

Also note that 'penis luigi' seems to have little to no effect on insane persons in general.)