The ALS Ice Bucket Challenge has quickly become an Internet phenomenon, and even country's biggest stars are joining the cause.

Created to raise awareness for the illness also known as Lou Gehrig's Disease, the challenge's popularity has grown rapidly.

Here's just a few of the country stars who have stepped up so far: Florida Georgia Line, Carrie Underwood, Taylor Swift, Eric Church, Tim McGraw, Faith Hill, Hunter Hayes, Dierks Bentley, Kip Moore, Justin Moore, Keith Urban, Lady Antebellum, Miranda Lambert, Shania Twain, The Band Perry and the Zac Brown Band. The list goes on and on.

The rules are simple: Those who are nominated have 24 hours to either donate funds to the ALS Association, or be doused with a bucket of ice water on camera.

Truly taking to the cause, many are doing both and finding more creative ways to drench themselves, like Underwood and husband Mike Fisher, who used a skid loader to get wet, or Zac Brown Band, who went even further and opted for a fire truck.

After the challenge is accepted and met, the participant can nominate three more people to partake -- which is how the sensation has spread so quickly.

Even CMT Hot 20 Countdown hosts Cody Alan and Katie Cook have gotten in on the act.

Aside from the fun of dousing your friends and family in freezing-cold water, the challenge has already made a major impact. Reports claim that funds raised so far are in excess of $22 million.

To learn more or contribute, visit ALSA.org and tune in to CMT Hot 20 Countdown this Saturday and Sunday (Aug. 23-24) at 11 a.m. ET/PT.