Wow, cool! Of course, I tried to get more info on pricing and following the booking link took me to a "Generic booking" page which, even flying into JFK and out of LCY, didn't show me the option, but I'd be really curious if I lived in NYC, for sure.

I've also had this issue with the "Premium Service" United flights between SFO and NYC/BOS. It supposedly exists, but whenever I search, I can't filter on those particular flights.