It used to be that the "tramp stamp" was the best way a woman could advertise her availability on her body, but teen girls in Australia have come up with a less permanent method -- painting their phone numbers on their backs in sunscreen.

A group of teen girls stirred up controversy when they were photographed on Australia's Manly Beach with their digits drawn in blue zinc cream on their bikini bods. Parents and police quickly pointed out that advertising your contact details in tan lines on your back isn't the safest way to make friends, but the girls insisted that their method is a great way to meet guys.

"We come for both the beaches and the boys, but I'm taken so it's all good," said one of the girls, Samantha.

Campaigner Nikki Goldstein said, "They're in their bikinis, showing off their bodies, objectifying themselves in a way that is, to my mind, a bit trashy."

We wouldn't go that far, but just to be safe, we'd ask that any adult women utilizing this pick-up method also paint a clear copy of her photo ID with visible date of birth.

Question Raised: Is the human billboard approach classless or convenient?