They apparently have Ashura processions around the world on that holiday. This year it will be on January 7th. Last year they actually had a procession in New York in January. A rather graphic video with blood is linked below from You Tube. Viewer beware.
Ashura New York January 2008
Apparently, the religious ceremonies alone that occur on Ashura are enough to cause some interest in this Islamic holiday. Not only do they flail themselves on the back, but they also have some ritual chest pounding. These ritual acts of self flagellation are called Matam. Here is a link to a Matam ritual that apparently occurred in New York in 2007. No blood here but interesting none-the-less.
Matam New York