It has become an urban phenomenon that has us looking to the skies and shaking our heads: Why exactly are those shoes dangling from power lines?

"I have no idea. I've never seen anyone put them there. I've just seen them show up," said Eric, while gazing at the pair of sneakers hanging above.

Drive around the University District in Seattle and you'll see many pairs of shoes overhead.

Tricia Manning-Smith

Why exactly are those shoes dangling from power lines?

Sightings are so common around the country that a Minneapolis-based Internet consultant even coined the term "shoefiti" to describe shoes or sneakers hanging by their laces from power or telephone lines.

But why waste good leather?

University of Washington student Roger shook his shoulders and said, "I'm open to interpretation."

Snopes.com offers some fodder to the debate. The Web site, which gives history behind urban legends, suggests many theories about shoefiti:

"It's the work of gangs marking the boundaries of their territory."

"Bullies take them off defenseless kids then sling them up out of reach as the ultimate taunt."

"Gang members create an informal memorial at the spot where a friend lost his life.”

"Crack dealers festoon wires to advertise their presence in the neighborhood."

"Graduating seniors mark this transition in their lives by leaving something of themselves behind; namely their shoes."

"Kids do it just because it's fun..."

Snopes.com explores the history of public shoe displays by elaborating on a Southwest practice: the sightings of worn boots upside down on roadside fence posts. Apparently, the angle of the boot toe indicates the boot owner's whereabouts. Meanwhile, some members of the military reportedly have a rite of "pitching an old pair of army boots over the wires when leaving a post."

But the bottom line is: No one really knows what turns people into shoe-slingers.

In Seattle's U-District, outside of the Sigma Kappa sorority, Christen says, "I kinda have a dirty meaning for it. They (fraternity boys) told me they do it whenever someone 'devirginizes' someone."

Well. That seems to tie-in with one final Snopes.com explanation:

"Overly puffed-up boys who have just lost their virginity or otherwise passed a sexual milestone" sling their shoes to "signal the event to others."

Yeah, that really proves their manliness.