But the youngest person thought to have taken part - and our particular favourite - is little Ianto, who decided to brave the cold when his mum Jane's cancer returned.
Jane, 40, was first diagnosed with a malignant melanoma in September 2009, when a pea-sized freckle was removed from her neck.
Despite all tests since coming back clear, sadly Jane discovered another lump this May and was told the cancer had returned.
This time it had spread to her lymph nodes and she needed surgery to remove it.
When Ianto was told, he was devastated. "I hate cancer," he told his dad, Shaun.
Wanting to suggest something positive to cheer up his son, Shaun suggested that Ianto did the ice challenge - and the little lad couldn't wait to take part.
Shaun couldn't bring himself to put ice in the bucket, so used lukewarm water instead, and heroic Ianto can be seen stood in a pair of green shorts as the water is poured over him.
For now, Jane's future is uncertain. While there are no tumours, doctors are unable to detect if there are still malignant cells in her body. So she's preparing by writing her will and planning letters to leave to her little boy if she loses her battle.
Ianto has taken part in the #IceBucketChallenge for Macmillan Cancer Support. Follow his lead and take on the challenge yourself, texting ICE to 70550 to donate £3 to Macmillan and upload your video to social media.
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