The iPhone, other than its tempting shininess that may make it a target for thieves, is a great travel tool. You can get travel apps, you can use it to listen to music to pass the time on long bus rides, and now, there’s a way to use it as a bottle opener.

From Yahoo News: two Australians have invented the Opena, a plastic case for the iPhone4 that includes a slide-out bottle opener.

The funding for the start-up was done online, and, according to their Facebook page, will be shipping in August or September. Cost is $39.95 (and I’m assuming that’s in Australian dollars). But if you go online to their Kickstarter site in the next 12 hours or so, you can become a backer for $30. As a backer, you’ll get an Opena.

“Basically, Australians are fairly heavy drinkers, as you may or may not know,” said Melbourne-based Chris Peters, an industrial designer who developed the product with Rob Ward, a former toolmaker.

“We’re always out at friends’ houses and so on, and in some cases you may not have your keys on you… So we thought, why don’t we attach a bottle opener to an iPhone case? We always have our phones on us.”

Working from three basic rules — the case had to be slim, there had to be no chance of the opener scratching the iPhone, and the opener had to work without putting any pressure on the phone — the two developed a prototype.

Testing including running through what a promotional video termed “the worst case scenario” in which a friend has shaken up the beer and it foams over. The case — and the iPhone — came through unscathed every time.

From a perhaps cynical perspective, my questions are how the manufacturing will work, and how many they are going to make. If the demand is large, it seems unlikely that a small start-up would be able to fill all its orders right away. But from a that’s awesome perspective, I think it’s great how two guys saw a gap in the market, figured out how to fill it, and got funding. And it brings together a lot of people’s favorite things – beer and their iPhone.

What do you think – good idea, or another random travel gadget that may seem cool, but isn’t really necessary?

For more on how it works, check out their video below, a parody of the Apple iPhone ad.