The No Pants Subway Ride is a yearly tradition started in 2002 by New York's Improv Everywhere that now takes place on train cars all over the world, from Los Angeles to Bucharest, Romania.
Participants in the No Pants Ride may cause fully clothed passengers to stare and sneer, and occasionally leer, but mostly this "international celebration of silliness" just makes people smile.
The No Pants Ride tradition is sure to keep spreading across the globe like the infections now spreading across the legs of the pantsless, and it will be interesting to see which country drops trou next!