PTKFGS
From YTMND
PTKFGS (Punch the Keys for Gods Sake), is a quote from Finding Forrester, and is said by Sean Connery shortly before he says the definitive YTMND line.
History
Being a line delivered in a similar sytle to YTMND, it was speculated as to what would have happened if PTKFGS was used instead of YTMND.
This was expanded on top of the Safety Not Guaranteed fad, in which the Time Traveler went back in time, and created an alternate Universe where YTMND is PTKFGS. This was further built into Alternate Universe Versions of Famous fads.