(No Pants Subway Ride 2010 in HD on YouTube)
From Improv Everywhere:
On Sunday, January 10th, 2010 over 5,000 people took off their pants on subways in 44 cities around the world. In New York, the 9th Annual No Pants! Subway Ride had over 3,000 participants, spread out over six meeting points and ten subway lines.
See the full report and photos: No Pants Subway Ride 2010