Washington: Steven Spielberg, Justin Bieber and Bill Gates are among many celebrities pouring buckets of ice water over their heads and donating to fight Lou Gehrig's disease, in a fundraising effort that has gone viral.
Since June, several thousand people worldwide have recorded themselves getting drenched, then posted the stunt online and challenged others to do the same, or pledge USD 100 to ALS research.
Many have done both, in an effort has raise millions of dollars for the ALS Association, which combats amyotrophic lateral sclerosis, also known as Lou Gehrig's disease.
Some 30,000 Americans have ALS, which attacks the nervous system and eventually leaves victims paralysed.
In just weeks the "ALS Ice Bucket Challenge" has swelled into a global phenomenon, with dozens of stars getting wet: Lady Gaga, Britney Spears, Justin Timberlake, Taylor Swift, James Franco, Oprah Winfrey, Jennifer Lopez and Jon Bon Jovi are among them.
Politicians and sports figures went at it too, including New Jersey Governor Chris Christie and basketball superstar LeBron James.