If you've logged onto Facebook, Twitter or Instagram, chances are your newsfeeds have been flooded with videos of people dumping buckets of ice water on their heads.
No, your friends aren't doing this to cool down from hot summer temperatures.
The challenge is a viral movement called the "Ice Bucket Challenge" designed to raise awareness for Amyotrophic Lateral Sclerosis, also known as ALS or Lou Gehrig's disease.
The challenge started in Massachusetts with former Boston College baseball player, Pete Frates, who was diagnosed with the disease in 2012.
ALS is a progressive neurodegenerative disease that affects nerve cells in the brain and spinal cord, leading to muscle weakness, loss of the use of arms and legs, and difficulty speaking, breathing and swallowing.
Frates, who can no longer speak, posted his own ice bucket challenge video to the tune of Vanilla Ice's "Ice, Ice Baby" and dared a few people to try it.
A social media firestorm ensued, extending well beyond the gates of Boston College.
After posting their ice bucket videos to social media, participants nominate others to take the plunge and keep the cycle going.
If those challenged don't accept within 24 hours, they're asked to donate to ALS research or to the charity of their choice.
Challenge accepted or not, donations have been pouring in.
According to the ALS Association spokeswoman, Carrie Munk, the organization has collected $1.35 million from July 29th to August 11th.
That's not counting donations to chapter offices around the country, Munk said.
During the same time period last year, donations totaled $22,000.
"The monetary contributions are amazing but there is so much value to the visibility that this is generating," Munk said. "It's unquantifiable."
On Thursday, Pete Frates' parents, Nancy and John, joined more than 200 Bostonians who took the Ice Bucket Challenge in Copley Square, challenging New York City, Los Angeles and Chicago to do the same.
According to The ALS Association, 50% of the American public doesn't know what the disease is.
But as Frates' story has spread, the Ice Bucket Challenge has become a call to arms for his family and friends to raise money and awareness for the disease, for which there is no cure.
"Who knew all it would take was a bag of ice and a bucket?" John Frates said.
So who has taken the Ice Bucket Challenge so far?
Martha Stewart, Ethel Kennedy (who has nominated President Obama), and many of your friends.
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