So there is finally a socially acceptable reason for men to post pictures of their penises on the Internet. The latest Instagram and Twitter trend is to upload a #cockinasock to raise awareness for testicular cancer.

Guys hang a sock from their penises, and post the pic online, adding the hashtag in hopes that someone will be inspired to go and get checked at a clinic.

The campaign was inspired by a similar project that had raised millions of dollars for the British nonprofit Cancer Research UK by asking women to post photos with no makeup.

"#Nomakeupselfie has raised awareness for breast cancer, and this is just an idea to generate a little bit of hype for the guys," says Siobhan Watton, who is working on the campaign with her cousin James Brown. "Our granddad is suffering from prostate and testicular cancer now. We want to raise awareness since male cancers don't get talked about as much as women's."

The family is trying to get more donations for Cancer Research UK and help educate men about the risks of testicular cancer in men under 40.

But what about Facebook? "Facebook has been a nightmare," says Watton. "They keep removing our pictures and closing our pages. But now that they've seen how massive it's gotten, more of the pictures are staying up."