Boker Tov has links to Atlas Shrugs, and Little Green Footballs.

Her caption for the links reads:  Everything you ever wanted to know about Ashoura.

I followed the links, and learned nothing new.

At Atlas Shrugs, they have a couple of stomach-churning pictures of flagellated Muslims.  The site also mentions that the holy day is to commemorate the martyrdom of Mohommad's grandson.  It also mentions that it celebrates the day Moses was delivered from Egypt, and the day Noah left the ark.

The Little Green Footballs link has even less information than that, but the pictures are more disturbing.

Yes, truly disturbing visuals, and surely the result of primitive and backward culture and misplaced devotion.  Truly, our revulsion at any religion that can practice such barbarity is well-place.  We should feel superior, and very, very smug.  It's a good thing none of "our" religions practice such barbarity...

...oh wait...never mind.  Turns out, Christians do it to.  That makes it OK, you know.  Below follows a quote from  Wikipedia:

[gross photo deleted, you can follow the link if you want to see it]

Flagellant in the misterie of Guardia Sanframondi

Modern processions of hooded Flagellants are still a feature of various Mediterranean Catholic countries, mainly in Spain, Portugal and Italy and some former colonies, usually every year during Lent. For example in the comune of Guardia Sanframondi in Campania, Italy, such parades are organized once every seven years.

In modern times, it has been speculated that the more extreme practices of mortification of the flesh may have been used to obtain altered states of consciousness for the goal of experiencing religious experiences or visions; medical research has shown that great pain releases endorphines which can have such effect, and even get some fetishists addicted to pain.

Some Christians in Philippines practice flagellation as a form of devout worship, sometimes in addition to self-crucifixion (during the end of Lent season).