Wooden roller coasters and zip-lines combine for some fancy flying shootouts in Bioshock Infinite.

The flying city of Columbia may be a technological marvel, but you need a way to get goods from Point A to Point B - and trucks aren't known for their ability to handle vertical inclines. So, the engineering wizards of the city invented the Sky-Line - an intra-city network that transports objects and people like a giant roller coaster.

But as Irrational Games' Ken Levine explains in the video here, Columbia's kids and thrill seekers discovered how to use hooks to ride the Sky-Line for fun. Once civil unrest broke out in the floating paradise, however, those who could ride the Sky-Lines became a valuable commodity - now as gunslingers.

This is a great little video, with Levine explaining some of his frustrations with the original BioShock - the surrounding ocean was really just art, and there was no real consideration given to how an underwater gunfight might feel - and talking about the genesis of the Sky-Line for Infinite.

There's also some fantastic footage of how the Sky-Lines work in-game, with the player jumping from one to another at will. I'm a sucker for clever movement schemes in games, and this just makes me all the more excited to check out Columbia for myself.

I also have the feeling that we're going to see some pretty insane trick videos on YouTube once this game comes out. Or is that just me?