Hugh Jackman, Ricky Gervais and the boys of 5SOS are just a few of the celebrities grabbing their crotches for the ‘Crotch Grab Challenge’ or #FeelingNuts.

Created by Check One Two, an organization dedicated to raising awareness and education for testicular cancer. The organization has declared October the month of the Crotch Grab Challenge to raise awareness and encourage men to check themselves – early detection can save lives.

#FeelingNuts

The idea is simple: post a crazy photo of yourself grabbing your crotch, post it online and challenge others to top your photo with the hashtag #FeelingNuts. Jackman took part in the challenge, posing for a crotch grabbing pic with a few friends.

Jackman also shared a slow-motion video of his crotch grab on Instagram and challenged Neil Patrick Harris, Michael Strahan and Ricky Gervais.

Gervais responded right away and passed the challenge along to William Shatner, and the trend is quickly spreading.