I'm never around for this. 
http://www.abs-cbnnews.com/global-filipino/01/12/12/no-pants-day-hits-ny-subways
NEW YORK, NY - Hundreds of train riders in different subway lines in New York took their pants off to participate in one of the biggest public pranks in the world known as the 2012 annual "No Pants Subway Ride".
It was started by Improv Everywhere founder Charlie Todd in 2001 with only 7 members in New York City. Now, the “No Pants Subway Ride” has grown, with thousands of participants that simultaneously drop their pants in 59 cities in 27 countries.
Second-time “No Pants Subway” rider Jaico Peralta said, “It was just so fun last year, I had to come back and experience it again.”
The idea is for pranksters to nonchalantly strip to their underwear from the waist down yet keeping their winter wear waist up to cause funny scenes in busy subway trains on a chilly Sunday afternoon.
Filipino subway rider Malou Reyes said, “Shocking, wala lang shocked talaga, akala ko siraulo, akala ko may tama eh, yun pala may event na ganun.”
“Some people looked with disgust, some people they liked it, they enjoyed it, they smiled, it’s pretty good time,” said Peralta.
For the dozens of Filipinos who joined in the prank, it was just another day to be silly and have loads of fun.
It was Tia Monera’s first time to join the prank, she said, “Pants are just uncomfortable sometimes, so we all decided to not wear them today.”
Keannu Martinez said, “They’re like, why are you wearing no pants? I’m like, ‘it got kinda hot like in the Philippines’.”
For Alexa Lorenzo, she said she had a blast. “It’s awesome, it’s liberating, I feel so free right now, it’s really good experience.”
Organizers said the point of Improv Everywhere is that there is no point. The “No Pants Subway Ride” is nothing but a collective prank that causes scenes of chaos and joy in public places.
http://www.abs-cbnnews.com/global-filipino/01/12/12/no-pants-day-hits-ny-subways