I've gotten hiccups from:
Snus--letting a bit of the juice get down my throat before I really tasted it
Getting a 'wet' hit on my PV, and swallowing about 1/2 drop worth of ejuice.
Occassionally while drinking a sweetened carbonated beverage (such as Coca Cola) through a straw.
Seems to be related to something getting just beyond the back of my tongue, and the hiccup seems to be the 'reflex'. So, the way I inhale from my PV could give *me* hiccups.
...picking up PV (clearomizer) to try...taking a puff, and allowing vapor to hit the back of my throat but *not* inhaling...HIC!
A sip of water seems to have calmed that down. I repeated the same 'method' with my carto-tank. HIC! One more time, with cartomizer. HIC!
OK....feels like vapor condensing at the back of my throat == swallowing nicotine. That's my observation, and fits the previous observations (except for the carbonated drink part...) I sometimes do a direct lung-inhale, and don't get hiccups, probably because the vapor does not get a chance to condense.
So...I'll agree with Rickajho's comment.