A paniced state of confusion where there are multiple obvious choices for courses of action, but the subject, overwhelmed and shocked, freezes up and does nothing.
Bill was flirting with this gorgeous babe all night then when she took her top off, he didn't know wether to shit or wind his watch!!!
Although a freindly parting salutation, this has it's roots planted firmly from the 70's pop culture of under-aged, underground consumption of marijuana and alchohol. This basically means: I have been talking for the last 5 minutes, and now realize that you are not only high, but not capable of understanding simple conversation, which, at this point, we can have at a later time, when you are not in such a state.
Hey bill, did you see that Kiss tickets go on sale on the 5th"Later When You're Straighter", dude!