Just read about the Star Wars thing on the subway. Funny, but what would they have done if some aspiring young Jedi had attempted to “save” the princess? I’m picturing say…a 6 year old…running up and bravely kicking the Sith Lord in the shin…
I daresay they would have improvised. 
I’m torn on picking a favorite, myself, but Frozen Grand Central and Moebius are way up there. This thread sent me on an IE binge, too.
I hadn’t seen the Star Wars one before today it’s great. I love the behind the scenes video and photos. In the caption under a photo of Vader waiting at a station it says that.
"Vader got all kinds of funny looks from people as they passed by or gawked at him from across the tracks. At one point, a young guy came up to him and said, “Sith Lord, would it be OK if I took your photo?” ’
That bolded part almost made me tear up. Sometimes I worry about the younger generations but it warms my heart to see that there still are kids out there who show their elders proper respect.
Since no one’s done this one yet, another favorite: Slo-Mo Home Depot. Basically involved the actors synchronizing watches, going into a Home Depot store, and at a set time they all started moving in slow motion. After five minutes, they resumed shopping normally. Then, after five more minutes, they all froze in place.
The kicker: by coincidence, just before they all froze, Jewel’s “Standing Still” started playing over the store intercom.