KAILUA, Hawaii -- If you drive around Oahu you've probably seen the U Down logo. It features a U with an arrow through the middle. It has been popping up all over the place -- even as far away as Iraq.

The company U Down is a clothing shop in Kailua. Its name came from its founders daring each other to do crazy stunts as in "are you down with that?"

"I have seen the 'U' signs and I've seen them on the highways, but I don't know what they are," Kailua resident Eileen Roether said.

The logo stickers are often seen on street signs, roads and buildings.

It turns out that the U Down has a meaning that its followers understand.

"U Down to do some crazy antics here? And there, that's the basis of our logo," a U Down company employee said.

Some of the crazy antics are displayed on the company's Web site. There are photos that show people climbing onto freeway signs among other things to put up the stickers.

Some people complain that vandalizing state highway signs costs taxpayers thousands of dollars a year. Police said that they are aware of the problem. However, they said it is a difficult one because they have to catch the person in the act in order to arrest them.

KITV asked a U Down employee if the company is encouraging vandalism by asking people to send in photos for its Web site.

"We encourage craziness. We don't promote the stickers everywhere. I've actually had to take stickers down that I see covering certain things that I can reach," the employee said.

The second-story shop is located on Uluniu Street in Kailua.

A Department Of Transportation spokesman said the state is aware of the vandalism, but declined to comment further.